Biography
Melanie Bell, PhD, MS is a Professor in the Department of Epidemiology and Biostatistics at the Mel and Enid Zuckerman College of Public Health, and the Head of the Biostatistics and Design core at the Center for Health Disparities Research, University of Arizona. She is the Vice-Chair of the Statistics Graduate Inter-Disciplinary Program, and holds an adjunct position at the University of Sydney. Her research focus is statistical methods for handling missing data in individual and cluster randomized trials, and the design and analysis of studies using patient reported outcomes. She is currently engaged in collaborative research in the fields of health disparities, chronic disease prevention, tobacco cessation and psycho-oncology. She has over 120 peer reviewed papers including 25 that are methodological. She has served on several data and safety monitoring boards, research advisory committees and grant review sections. Dr Bell has mentored individuals ranging from undergraduates to post-docs and junior faculty, and has served on mentoring committees for successful K-awards. Dr. Bell earned her PhD in Biostatistics from the University of Colorado Health Sciences Center in 2002, an MS in Mathematics in 1992 from Northern Arizona University, and an AB in Mathematics from Occidental College in Los Angeles, in 1990.
Degrees
- Ph.D. Biostatistics
- University of Colorado Health Sciences Center, Denver, Colorado, United States
- The use of maximum pseudolikelihood in generalized linear mixed models for the analysis of replicated spatial point patterns.
- M.S. Mathematics
- Northern Arizona University, Flagstaff, Arizona, United States
- B.A. Mathematics
- Occidental College, Los Angeles, California, United States
Work Experience
- University of Arizona, Tucson, Arizona (2013 - Ongoing)
- University of Sydney (2013 - Ongoing)
- University of Sydney (2013 - Ongoing)
- University of Otago (2003 - 2009)
Awards
- MEZCOPH research award
- College of Public Health, Spring 2019
- Dean's Fund Travel Award
- MEZCOPH Dean, Spring 2016
- Enthusiasm For Teaching
- MEZCOPH Division of Epidemiology & Biostatistics, Fall 2014
Interests
Research
Missing data in clinical trialsCluster randomized trialsDesign and analysis of studies using patient reported outcomes
Courses
2021-22 Courses
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Clin Trials+Intervnt Std
BIOS 675 (Spring 2022) -
Clin Trials+Intervnt Std
EPID 675 (Spring 2022) -
Appld Biostat Analysis
BIOS 576C (Fall 2021) -
Research
BIOS 900 (Fall 2021) -
Thesis
STAT 910 (Fall 2021)
2020-21 Courses
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Research
BIOS 900 (Summer I 2021) -
Clin Trials+Intervnt Std
BIOS 675 (Spring 2021) -
Clin Trials+Intervnt Std
EPID 675 (Spring 2021) -
Thesis
BIOS 910 (Spring 2021) -
Appld Biostat Analysis
BIOS 576C (Fall 2020) -
Thesis
BIOS 910 (Fall 2020) -
Thesis
STAT 910 (Fall 2020)
2019-20 Courses
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Appld Biostat Analysis
BIOS 576C (Fall 2019)
2018-19 Courses
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Clin Trials+Intervnt Std
BIOS 675 (Spring 2019) -
Clin Trials+Intervnt Std
EPID 675 (Spring 2019) -
Dissertation
BIOS 920 (Spring 2019) -
Dissertation
STAT 920 (Spring 2019) -
Master's Report
BIOS 909 (Spring 2019) -
Thesis
BIOS 910 (Spring 2019) -
Appld Biostat Analysis
BIOS 576C (Fall 2018) -
Dissertation
BIOS 920 (Fall 2018) -
Dissertation
STAT 920 (Fall 2018) -
Master's Report
BIOS 909 (Fall 2018) -
Thesis
BIOS 910 (Fall 2018)
2017-18 Courses
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Dissertation
BIOS 920 (Spring 2018) -
Dissertation
STAT 920 (Spring 2018) -
Research
STAT 900 (Spring 2018) -
Thesis
BIOS 910 (Spring 2018) -
Appld Biostat Analysis
BIOS 576C (Fall 2017) -
Research
BIOS 900 (Fall 2017) -
Research
STAT 900 (Fall 2017) -
Thesis
BIOS 910 (Fall 2017)
2016-17 Courses
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Thesis
CPH 910 (Summer I 2017) -
Clin Trials+Intervnt Std
CPH 675 (Spring 2017) -
Master's Report
CPH 909 (Spring 2017) -
Research
CPH 900 (Spring 2017) -
Thesis
CPH 910 (Spring 2017) -
Appld Biostat Analysis
CPH 576C (Fall 2016) -
Appld Biostat Analysis
EPID 576C (Fall 2016) -
Evaluat Public Hlth Literature
CPH 609 (Fall 2016) -
Independent Study
CPH 599 (Fall 2016) -
Master's Report
CPH 909 (Fall 2016) -
Thesis
CPH 910 (Fall 2016)
2015-16 Courses
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Master's Report
CPH 909 (Summer I 2016) -
Clin Trials+Intervnt Std
CPH 675 (Spring 2016) -
Clin Trials+Intervnt Std
EPID 675 (Spring 2016) -
Dissertation
EPID 920 (Spring 2016) -
Master's Report
CPH 909 (Spring 2016) -
Preceptorship
CPH 491 (Spring 2016) -
Thesis
CPH 910 (Spring 2016)
Scholarly Contributions
Journals/Publications
- Bell, M. L., Catalfamo, C. J., Farland, L. V., Ernst, K. C., Jacobs, E. T., Klimentidis, Y. C., Jehn, M., & Pogreba-Brown, K. (2021). Post-acute sequelae of COVID-19 in a non-hospitalized cohort: results from the Arizona CoVHORT. medRxiv.
- Catalfamo, C. J., Heslin, K. M., Shilen, A., Khan, S. M., Hunsaker, J. R., Austhof, E., Barraza, L., Cordova-Marks, F. M., Farland, L. V., & Garcia-Filion, P. (2021). Design of the Arizona CoVHORT: A Population-Based COVID-19 Cohort. Frontiers in Public Health, 9, 21.
- Coulter, K., Ingram, M., Lohr, A. M., Bell, M. L., & Carvajal, S. (2021). Examining Associations between Community Health Worker-Rated Health and Mental Health among Latino Adults with Chronic Disease. International journal of environmental research and public health, 18(1), 100.
- Gordon, J. S., Bell, M. L., Armin, J. S., Giacobbi, P. R., & Nair, U. S. (2021). A telephone-based guided imagery tobacco cessation intervention: results of a randomized feasibility trial. Translational behavioral medicine, 11(2), 516-529.
- Gordon, J. S., Nair, U. S., Gordon, J. S., Giacobbi, P. R., Bell, M. L., & Armin, J. S. (2021). A telephone-based guided imagery tobacco cessation intervention: results of a randomized feasibility trial.. Translational behavioral medicine, 11(2), 516-529. doi:10.1093/tbm/ibaa052More infoEvidence supports the use of guided imagery for smoking cessation; however, scalable delivery methods are needed to make it a viable approach. Telephone-based tobacco quitlines are a standard of care, but reach is limited. Adding guided imagery to quitline services might increase reach by offering an alternative approach..To develop and test the feasibility and potential impact of a guided imagery-based tobacco cessation intervention delivered using a quitline model..Participants for this randomized feasibility trial were recruited statewide through a quitline or community-based methods. Participants were randomized to guided imagery Intervention Condition (IC) or active behavioral Control Condition (CC). After withdrawals, there were 105 participants (IC = 56; CC = 49). The IC consisted of six sessions in which participants created guided imagery audio files. The CC used a standard six-session behavioral protocol. Feasibility measures included recruitment rate, retention, and adherence to treatment. We also assessed 6-month quit rates and consumer satisfaction..Both the IC and CC protocols were feasible to deliver. We finalized protocols and materials for participants, coaches and study staff, and delivered the protocols with fidelity. We developed successful recruitment methods, and experienced high retention (6 months = 81.9%) and adherence (all sessions = 66.7%). Long-term quit rates (IC = 27.9%; CC = 38.1%) compared favorably to those of quitlines, and program satisfaction was high, suggesting that the protocols are acceptable to smokers and may contribute to smoking abstinence..The guided imagery intervention is feasible and promising, suggesting that a fully powered RCT to test the efficacy of the intervention is warranted..NCT02968381.
- Gutenkunst, S. L., Vardy, J. L., Dhillon, H. M., & Bell, M. L. (2021). Correlates of cognitive impairment in adult cancer survivors who have received chemotherapy and report cognitive problems. Supportive Care in Cancer, 29(3), 1377-1386.
- Haynes, P. L., Silva, G. E., Quan, S. F., Mcmorrow, T. E., Haynes, P. L., Bell, M. L., & Bautista, R. (2021). Association between obstructive sleep apnea and multiple involuntary job loss history among recently unemployed adults.. Sleep health, 7(1), 118-122. doi:10.1016/j.sleh.2020.08.002More infoObstructive sleep apnea (OSA) has been associated with negative occupational outcomes including absenteeism and poor work productivity. This analysis explored whether the severity of OSA was associated with multiple involuntary job loss history among recently unemployed adults..This is a cross-sectional analysis of data from the screening visit of the Assessing Daily Activity Patterns Through Occupational Transitions study. Information was collected from 261 participants who recently involuntarily lost their jobs. Data included demographics, employment, medical history, and results from a limited channel home sleep apnea test. The respiratory event index was categorized as
- Jung, A. M., Jahnke, S. A., Dennis, L. K., Bell, M. L., Burgess, J. L., Jitnarin, N., Kaipust, C. M., & Farland, L. V. (2021). Occupational factors and miscarriages in the US fire service: a cross-sectional analysis of women firefighters. Environmental Health, 20(1), 1-13.
- Lee, K. J., Tilling, K. M., Cornish, R. P., Little, R. J., Bell, M. L., Goetghebeur, E., Hogan, J. W., & Carpenter, J. R. (2021). Framework for the treatment and reporting of missing data in observational studies: The Treatment And Reporting of Missing data in Observational Studies framework. Journal of clinical epidemiology, 134, 79-88.
- Muramoto, M. L., Hopkins, A., Bell, M., Allen, A., Nair, U., & Connolly, T. E. (2021). Results of a feasibility study of helpers stay quit training for smoking relapse prevention. Nicotine and Tobacco Research, 23(4), 711-715.
- Nair, U. S., Muramoto, M. L., Hopkins, A. L., Connolly, T. E., Bell, M. L., & Allen, A. M. (2021). Results of a Feasibility Study of Helpers Stay Quit Training for Smoking Relapse Prevention.. Nicotine & tobacco research : official journal of the Society for Research on Nicotine and Tobacco, 23(4), 711-715. doi:10.1093/ntr/ntaa176More infoMost smoking quit attempts end in relapse, and interventions focused on relapse prevention are lacking. Helpers Stay Quit (HSQ) is a novel behavioral relapse prevention intervention that teaches newly abstinent smokers to offer a "helping conversation" (HC) to help others quit tobacco..Pre-post intervention feasibility study with state quitline participants ≥14 days abstinent. Measures at baseline, 3 months, and 6 months included smoking status, offering HCs, and cessation self-efficacy. Primary outcomes: self-reported 7-day point prevalence abstinence; offering HCs. Cox models explored association of HCs with relapse. Preliminary effects analysis using propensity score matching compared 30-day abstinence of quitline clients with study sample at 7 months..Participants (N = 104) were as follows: mean age of 53 years (SD 13.9 years), 48.1% male, mean of cigarettes smoked/day of 16.2 (SD 9.7). Compared with participants who remained abstinent (n = 82), relapsers (n = 22) had fewer HCs over 6 months (2.6 vs 7.2; 95% confidence interval [CI]: 1.4, 7.8, p = .006). Using adjusted Cox regression, the hazard ratio of relapse for each HC was 0.85 (95% CI: 0.74, 0.99, p = .03). Compared with a matched sample of quitline clients not exposed to HSQ, study participants were 49% more likely to report 30-day abstinence at 7-month quitline follow-up (95% CI: 40%, 59%, p < .0001)..HSQ, delivered to newly abstinent smokers who received standard quitline treatment, was associated with less self-reported relapse. These promising preliminary study results warrant further research to evaluate HSQ as a novel behavioral intervention to prevent smoking relapse..To date, behavioral interventions for smoking relapse prevention that teach abstainers cessation skills to apply to themselves have not shown effectiveness. This feasibility study examines the preliminary efficacy of a conceptually novel, "help others" behavioral intervention approach for relapse prevention in newly abstinent smokers recruited from a state quitline. HSQ teaches the newly abstinent smoker communication and listening skills to encourage other smokers in their personal social network to quit. Exploratory analysis using propensity score matching suggests that participants exposed to HSQ were significantly more likely to self-report 30-day abstinence at quitline 7-month follow-up than other quitline clients.
- Pogreba-brown, K., Lutrick, K., Harris, R. B., Farland, L. V., Cordova-marks, F. M., Shilen, A., Pogreba-brown, K., Lutrick, K., Kohler, L. N., Klimentidis, Y. C., Khan, S. M., Jehn, M., Jacobs, E. T., Hunsaker, J. R., Hoskinson, J., Heslin, K. M., Harris, R. B., Garcia-filion, P., Farland, L. V., , Ernst, K. C., et al. (2021). Design of the Arizona CoVHORT: A Population-Based COVID-19 Cohort.. Frontiers in public health, 9, 620060. doi:10.3389/fpubh.2021.620060More infoThis study is a prospective, population-based cohort of individuals with a history of SARS-CoV-2 infection and those without past infection through multiple recruitment sources. The main study goal is to track health status over time, within the diverse populations of Arizona and to identify the long-term consequences of COVID-19 on health and well-being. A total of 2,881 study participants (16.2% with a confirmed SARS-CoV-2 infection) have been enrolled as of December 22, 2020, with a target enrollment of 10,000 participants and a planned follow-up of at least 2 years. This manuscript describes a scalable study design that utilizes a wide range of recruitment sources, leveraging electronic data collection to capture and link longitudinal participant data on the current and emerging issues associated with the COVID-19 pandemic. The cohort is built within a collaborative infrastructure that includes new and established partnerships with multiple stakeholders, including the state's public universities, local health departments, tribes, and tribal organizations. Challenges remain for ensuring recruitment of diverse participants and participant retention, although the electronic data management system and timing of participant contact can help to mitigate these problems.
- Rosales, C. B., Denman, C. A., Bell, M. L., Cornejo, E., Ingram, M., del, C., Gonzalez-Fagoaga, J., Aceves, B., Nuño, T., & Anderson, E. J. (2021). Meta Salud Diabetes for cardiovascular disease prevention in Mexico: a cluster-randomized behavioural clinical trial. International Journal of Epidemiology.
- Roydhouse, J. K., Floden, L., Tomko, R. L., Gray, K. M., & Bell, M. L. (2021). The estimand framework and its application in substance use disorder clinical trials: a case study. The American journal of drug and alcohol abuse, 1-6.
- Silva, G. E., Quan, S. F., McMorrow, T., Bautista, R., Bell, M. L., & Haynes, P. L. (2021). Association between obstructive sleep apnea and multiple involuntary job loss history among recently unemployed adults. Sleep Health, 7(1), 118-122.
- Teufel-shone, N. I., Lothrop, N., Horne, Y. O., Chief, K., Charley, P. H., Canales, R. A., Bell, M. L., Begay, M., & Beamer, P. I. (2021). Impacts to Diné activities with the San Juan River after the Gold King Mine Spill.. Journal of Exposure Science and Environmental Epidemiology, 1-15. doi:10.1038/s41370-021-00290-zMore infoBACKGROUND On August 5th, 2015, 3 million gallons of acid mine drainage was accidentally discharged from the Gold King Mine near Silverton, Colorado into Cement Creek which is a tributary to the Animas and San Juan Rivers. The government-initiated risk assessment only assessed a recreational scenario (i.e. hiker drinking from the river), failing to recognize the deep connection of the Dine (Navajo) with the San Juan River. METHODS Utilizing a mixed-methods approach we determined the impacts of the 2015 Gold King Mine Spill (GKMS or Spill) on Dine activities. We developed a questionnaire to collect pre- and post-GKMS Dine activity frequency and duration. Navajo Nation Community Health Representatives administered the questionnaire to 63 Dine adults and 27 children living in three Navajo communities along the River. RESULTS Through analysis of the focus group transcripts we identified 43 unique activities between the Dine and San Juan River. There were significant reductions in the total number, frequency, and duration of livelihood, dietary, recreational, cultural/spiritual and arts and craft activities. On average, Dine activities with the San Juan River following the GKMS decreased by 56.2%. SIGNIFICANCE The significant reduction in activities following the GKMS may lead to long-term trauma, impacting the ability of the Dine to pass down teachings to their children affecting future generations to come. The 43 distinct activities between the Dine and the San Juan River highlight the importance for scientists and disaster responders to consider cultural and spiritual impacts when responding to environmental disasters and conducting risk assessments among Indigenous communities.
- Teufel-shone, N. I., Lothrop, N., Horne, Y. O., Chief, K., Charley, P. H., Canales, R. A., Bell, M. L., Begay, M., & Beamer, P. I. (2021). Impacts to Diné activities with the San Juan River after the Gold King Mine Spill.. Journal of exposure science & environmental epidemiology, 1-15. doi:10.1038/s41370-021-00290-zMore infoOn August 5th, 2015, 3 million gallons of acid mine drainage was accidentally discharged from the Gold King Mine near Silverton, Colorado into Cement Creek which is a tributary to the Animas and San Juan Rivers. The government-initiated risk assessment only assessed a recreational scenario (i.e. hiker drinking from the river), failing to recognize the deep connection of the Diné (Navajo) with the San Juan River..Utilizing a mixed-methods approach we determined the impacts of the 2015 Gold King Mine Spill (GKMS or Spill) on Diné activities. We developed a questionnaire to collect pre- and post-GKMS Diné activity frequency and duration. Navajo Nation Community Health Representatives administered the questionnaire to 63 Diné adults and 27 children living in three Navajo communities along the River..Through analysis of the focus group transcripts we identified 43 unique activities between the Diné and San Juan River. There were significant reductions in the total number, frequency, and duration of livelihood, dietary, recreational, cultural/spiritual and arts and craft activities. On average, Diné activities with the San Juan River following the GKMS decreased by 56.2%..The significant reduction in activities following the GKMS may lead to long-term trauma, impacting the ability of the Diné to pass down teachings to their children affecting future generations to come. The 43 distinct activities between the Diné and the San Juan River highlight the importance for scientists and disaster responders to consider cultural and spiritual impacts when responding to environmental disasters and conducting risk assessments among Indigenous communities.
- Tilling, K. M., Little, R. J., Lee, K. J., Hogan, J. W., Goetghebeur, E., Cornish, R. P., Carpenter, J. R., & Bell, M. L. (2021). Framework for the treatment and reporting of missing data in observational studies: The Treatment And Reporting of Missing data in Observational Studies framework.. Journal of clinical epidemiology, 134, 79-88. doi:10.1016/j.jclinepi.2021.01.008More infoMissing data are ubiquitous in medical research. Although there is increasing guidance on how to handle missing data, practice is changing slowly and misapprehensions abound, particularly in observational research. Importantly, the lack of transparency around methodological decisions is threatening the validity and reproducibility of modern research. We present a practical framework for handling and reporting the analysis of incomplete data in observational studies, which we illustrate using a case study from the Avon Longitudinal Study of Parents and Children. The framework consists of three steps: 1) Develop an analysis plan specifying the analysis model and how missing data are going to be addressed. An important consideration is whether a complete records' analysis is likely to be valid, whether multiple imputation or an alternative approach is likely to offer benefits and whether a sensitivity analysis regarding the missingness mechanism is required; 2) Examine the data, checking the methods outlined in the analysis plan are appropriate, and conduct the preplanned analysis; and 3) Report the results, including a description of the missing data, details on how the missing data were addressed, and the results from all analyses, interpreted in light of the missing data and the clinical relevance. This framework seeks to support researchers in thinking systematically about missing data and transparently reporting the potential effect on the study results, therefore increasing the confidence in and reproducibility of research findings.
- Van, H., Chief, K., Charley, P. H., Begay, M., Lothrop, N., Bell, M. L., Canales, R. A., Teufel-Shone, N. I., & Beamer, P. I. (2021). Impacts to Diné activities with the San Juan River after the Gold King Mine Spill. Journal of Exposure Science & Environmental Epidemiology, 1-15.
- Vardy, J., Gutenkunst, S. L., Dhillon, H. M., & Bell, M. L. (2021). Correlates of cognitive impairment in adult cancer survivors who have received chemotherapy and report cognitive problems.. Supportive Care in Cancer, 29(3), 1377-1386. doi:10.1007/s00520-020-05616-5More infoObjective Cognitive impairment negatively affects some cancer survivors who have completed chemotherapy; however, factors underlying this cognitive impairment remain poorly understood. We aimed to investigate (1) the relative importance of demographics, medical, and psychological characteristics associated with cognitive impairment and (2) the specific variables associated with cognitive impairment in adult cancer survivors who completed adjuvant chemotherapy. Methods We performed post hoc analyses of baseline data from early-stage cancer survivors with cognitive complaints who received adjuvant chemotherapy 0.5-5 years earlier and volunteered for a trial designed to improve cognition. The primary outcome of self-reported cognitive impairment was measured using a questionnaire; secondary outcome of objective cognitive impairment was measured using a computerized neuropsychological test battery. Hierarchical linear regression determined the relative importance of demographics, medical, and psychological characteristics in associations with both self-reported and objective cognitive impairment. Results The sample was 95% female and 89% breast cancer patients. The final model accounted for 33% of variation in self-reported cognitive impairment (n = 212, demographics 5%, medical 3%, and psychological 25%), with fatigue and stress as significant individual correlates (p values ≤ 0.0001). For the secondary analysis, the final model accounted for 19% of variation in objective cognitive impairment (n = 206, demographics 10%, medical 5%, and psychological 4%), with age, smoking history, and number of chemotherapy cycles as significant individual correlates. Conclusion We found that psychological characteristics are more important than demographic and medical characteristics in self-reported cognitive impairment, whereas other characteristics are more important in objective cognitive impairment. This suggests clinicians should investigate possible psychological problems in cancer survivors who self-report cognitive impairment.
- Zapien, J. G., Vasquez, M. D., Rosales, C. B., Nuno, T., Ingram, M., Gonzalez-fagoaga, J. E., Denman, C. A., Cornejo, E., Bell, M. L., Anderson, E. J., & Aceves, B. (2021). Meta Salud Diabetes for cardiovascular disease prevention in Mexico: a cluster-randomized behavioural clinical trial.. International journal of epidemiology. doi:10.1093/ije/dyab072More infoHealthy lifestyle interventions offered at points of care, including support groups, may improve chronic disease management, especially in low-resource populations. We assessed the effectiveness of an educational intervention in type 2 diabetes (T2D) support groups to reduce cardiovascular disease (CVD) risk..We recruited 518 participants to a parallel, two-arm, cluster-randomized, behavioural clinical trial across 22 clinics in Sonora, Mexico, between August 2016 and October 2018. We delivered a 13-week secondary prevention intervention, Meta Salud Diabetes (MSD), within the structure of a support group (GAM: Grupo de Ayuda Mutua) in government-run (community) Health Centres (Centros de Salud). The primary study outcomes were difference in Framingham CVD risk scores and hypertension between intervention (GAM+MSD) and control (GAM usual care) arms at 3 and 12 months..CVD risk was 3.17% age-points lower in the MSD arm versus control at 3 months [95% confidence interval (CI): -5.60, -0.75, P = 0.013); at 12 months the difference was 2.13% age-points (95% CI: -4.60, 0.34, P = 0.088). There was no evidence of a difference in hypertension rates between arms. Diabetes distress was also lower at 3 and 12 months in the MSD arm. Post-hoc analyses showed greater CVD risk reduction among men than women and among participants with HbA1c < 8..MSD contributed to a positive trend in reducing CVD risk in a low-resource setting. This study introduced an evidence-based curriculum that provides T2D self-management strategies for those with controlled T2D (i.e. HbA1c < 8.0) and may improve quality of life.
- Anderson, E. J., Chebet, J. J., Asaolu, I. O., Bell, M. L., & Ehiri, J. (2020). Influence of Women’s Empowerment on Place of Delivery in North Eastern and Western Kenya: A Cross-sectional Analysis of the Kenya Demographic Health Survey. Journal of epidemiology and global health, 10(1), 65.
- Bell, M. L., & Rabe, B. A. (2020). The mixed model for repeated measures for cluster randomized trials: a simulation study investigating bias and type I error with missing continuous data. Trials, 21(1), 148.
- Chebet, J. J., Thomson, C. A., Kohler, L. N., Ehiri, J. E., Luo, J., Cheng, T. D., Pan, K., Chlebowski, R. T., Nassir, R., Sealy-Jefferson, S., & others, . (2020). Association of diet quality and physical activity on obesity-related cancer risk and mortality in Black women: Results from the Women's Health Initiative. Cancer Epidemiology and Prevention Biomarkers, 29(3), 591--598.
- Gordon, J. S., Bell, M. L., Armin, J. S., Giacobbi, P. R., & Nair, U. S. (2020). A telephone-based guided imagery tobacco cessation intervention: results of a randomized feasibility trial. Translational Behavioral Medicine.
- Gutenkunst, S. L., Vardy, J. L., Dhillon, H. M., & Bell, M. L. (2020). Correlates of cognitive impairment in adult cancer survivors who have received chemotherapy and report cognitive problems. Supportive Care in Cancer, 1--10.
- Lohr, A. M., Carvajal, S. C., Lohr, A. M., Ingram, M., Coulter, K., Carvajal, S. C., & Bell, M. L. (2020). Examining Associations between Community Health Worker-Rated Health and Mental Health among Latino Adults with Chronic Disease.. International journal of environmental research and public health, 18(1). doi:10.3390/ijerph18010100More infoLatinos with chronic disease often experience comorbid depression, but confront barriers to mental health treatment. Community health workers (CHWs) develop trusting relationships with the communities they serve, and may be uniquely positioned to identify Latinos with mental health care needs. Research has not examined whether their rating of clients' health is indicative of their mental health. This mixed-methods study examines CHWs' appraisals of Latino adults' health and their relation to mental health outcomes, and explores factors informing CHWs' rating of health status. The current study utilized baseline data from the Linking Individual Needs to Community and Clinical Services (LINKS) study. We assessed associations between CHW-rated health (CHWRH), or rating of health status as poor-excellent, and mental health outcomes with multilevel linear regression modelling. We qualitatively analyzed CHWs' written perceptions of participants' health status to understand what influenced their health rating. The quantitative results showed that CWHRH was significantly related to depressive symptoms and emotional problems severity. The qualitative results showed that CHWs took a holistic and ecological approach in rating health. The findings suggest that CHWRH could be indicative of mental health among Latino adults. Further studies investigating CHWRH as an independent indicator of mental health are warranted.
- Miller, M. L., Roe, D. J., Hu, C., & Bell, M. L. (2020). Power difference in a $chi$ 2 test vs generalized linear mixed model in the presence of missing data--a simulation study. BMC medical research methodology, 20(1), 1--12.
- Muramoto, M. L., Hopkins, A., Bell, M., Allen, A., Nair, U., & Connolly, T. E. (2020). Results of a feasibility study of Helpers Stay Quit Training for smoking relapse prevention. Nicotine & Tobacco Research.
- Nair, U. S., Miller, E. S., Bell, M. L., Allen, S., Collins, B. N., & Allen, A. M. (2020). Feasibility and Acceptability of Timing a Quit Attempt to the Menstrual Phase in a Telephone-Based Smoking Cessation Intervention: Protocol of a Pilot Randomized Controlled Trial. Nicotine and Tobacco Research.
- Nair, U. S., Miller, E. S., Bell, M. L., Allen, S., Collins, B. N., & Allen, A. M. (2020). Feasibility and acceptability of testing a menstrual-cycle timed smoking cessation intervention for women of reproductive age (Project Phase): Protocol of a pilot randomized controlled trial. Contemporary Clinical Trials Communications, 18, 100569.
- Nair, U. S., Rabe, B., Brady, B. R., & Bell, M. L. (2020). Predictors of client retention in a state-based tobacco quitline. Journal of Smoking Cessation, 15(2), 67--75.
- Rabe, B. A., & Bell, M. L. (2020). A Conservative Approach for Analysis of Noninferiority Trials With Missing Data and Subject Noncompliance. Statistics in Biopharmaceutical Research, 12(2), 176--186.
- Silva, G. E., Quan, S. F., McMorrow, T., Bautista, R., Bell, M. L., & Haynes, P. L. (2020). Association between obstructive sleep apnea and multiple involuntary job loss history among recently unemployed adults. Sleep Health.
- Smith-Uffen, M., Johnson, S. B., Martin, A. J., Tattersall, M., Stockler, M. R., Bell, M. L., Detering, K., Clayton, J. M., Silvester, W., Clarke, S., & others, . (2020). Estimating survival in advanced cancer: a comparison of estimates made by oncologists and patients. Supportive Care in Cancer, 28(7), 3399--3407.
- Trejo, M. J., Bell, M. L., Dhillon, H. M., & Vardy, J. L. (2020). Baseline quality of life is associated with survival among people with advanced lung cancer. Journal of psychosocial oncology, 38(5), 635--641.
- Trejo, M. J., Lishimpi, K., Kalima, M., Mwaba, C. K., Banda, L., Chuba, A., Chama, E., Msadabwe, S. C., Bell, M. L., Harris, R. B., & others, . (2020). Effects of HIV status on non-metastatic cervical cancer progression among patients in Lusaka, Zambia. International Journal of Gynecologic Cancer, 30(5).
- Yuan, N. P., Schultz, J. L., Nair, U. S., & Bell, M. L. (2020). Predictors of Tobacco Cessation Among American Indian/Alaska Native Adults Enrolled in a State Quitline. Substance use & misuse, 55(3), 452--459.
- Barrett, E., Carr, D., Bell, M. L., & Pogreba Brown, K. M. (2018). Pilot Study of Long-Term Sequelae following a Campylobacteriosis Infection. Submitted to Pilot and Feasibility Studies. Pilot and Feasibility Studies.
- Bell, M. L., Floden, L., Rabe, B. A., Hudgens, S., Dhillon, H. M., Bray, V. J., & Vardy, J. L. (2019). Analytical approaches and estimands to take account of missing patient-reported data in longitudinal studies. Patient related outcome measures, 10, 129.
- Floden, L., & Bell, M. L. (2019). Imputation strategies when a continuous outcome is to be dichotomized for responder analysis: a simulation study. BMC medical research methodology, 19(1), 161.
- Garcia, D. O., Morrill, K. E., Aceves, B., Valdez, L. A., Rabe, B. A., Bell, M. L., Hakim, I. A., Martinez, J. A., & Thomson, C. A. (2019). Feasibility and acceptability of a beverage intervention for Hispanic adults: results from a pilot randomized controlled trial. Public health nutrition, 22(3), 542-552.
- Gordon, J. S., Giacobbi Jr, ,., Armin, J. S., Nair, U. S., Bell, M. L., & Povis, G. (2019). Testing the feasibility of a guided imagery tobacco cessation intervention delivered by a telephone quitline: Study protocol for a randomized controlled feasibility trial. Contemporary Clinical Trials Communications, 16, 100437.
- Ingram, M., Marrone, N. L., & Bell, M. L. (2018). Self-reported hearing difficulty and its association with general, cognitive, and psychosocial health in the state of Arizona, 2015. BMC Public Health.
- Lohr, A. M., Ingram, M., Carvajal, S. C., Doubleday, K., Aceves, B., Espinoza, C., Redondo, F., Coronado, G., David, C., & Bell, M. L. (2019). Protocol for LINKS (linking individual needs to community and clinical services): a prospective matched observational study of a community health worker community clinical linkage intervention on the US-Mexico border. BMC public health, 19(1), 399.
- Marrone, N., Ingram, M., Bischoff, K., Burgen, E., Carvajal, S. C., & Bell, M. L. (2019). Self-reported hearing difficulty and its association with general, cognitive, and psychosocial health in the state of Arizona, 2015. BMC public health, 19(1), 875.
- Nair, U. S., Reikowsky, R. C., Allen, A. M., & Bell, M. L. (2019). Quitline program utilization and cessation outcomes: A comparison of provider-referred clients by healthcare settings. Preventive Medicine Reports, 14, 100863.
- Peterson, R. L., Carvajal, S. C., McGuire, L. C., Fain, M. J., & Bell, M. L. (2019). State inequality, socioeconomic position and subjective cognitive decline in the United States. SSM-population health, 7, 100357.
- Rabe, B. A., & Bell, M. L. (2019). A Conservative Approach for Analysis of Noninferiority Trials With Missing Data and Subject Noncompliance. Statistics in Biopharmaceutical Research, 1-11.
- Smith-Uffen, M. E., Johnson, S. B., Martin, A. J., Tattersall, M., Stockler, M. R., Bell, M. L., Detering, K., Clayton, J. M., Silvester, W., & Clarke, S. (2019). Estimating survival in advanced cancer: a comparison of estimates made by oncologists and patients. Supportive Care in Cancer, 1-9.
- Vaccaro, L., Butow, P. N., Lee, D., Johnson, S. B., Bell, M., Clayton, J., Detering, K. M., & Tattersall, M. (2019). Fidelity is fundamental: intervention predictors in advance care plans in terminal cancer. BMJ supportive & palliative care, 9(4), 397-403.
- Valdez, L., Garcia, D., Aceves, B., Bell, M., Humphrey, K., Hingle, M., McEwen, M., & Hooker, S. (2019). A Gender-and Culturally Sensitive Weight Loss Intervention for Hispanic Men: Results From theAnimoPilot Randomized Controlled Trial. Health Education & Behavior, 46(5), 763-772.
- Wagoner, R., Pogreba-Brown, K., Barrett, E., & Bell, M. (2019). Campylobacter and Laboratory Analysis Type: A Case-Case Analysis to Determine Differences in Risk Factors. Environmental Epidemiology, 3, 419.
- Yuan, N. P., Krupski, L., Yuan, N. P., Wertheim, B. C., Nair, U. S., Krupski, L., Bell, M. L., & Allen, A. M. (2019). Gender differences in utilization of services and tobacco cessation outcomes at a state quitline.. Translational behavioral medicine, 9(4), 663-668. doi:10.1093/tbm/iby083More infoResearch suggests that women may have poorer tobacco cessation outcomes than men; however, the literature is somewhat mixed. Less is known about gender differences in cessation within quitline settings. This study examined gender differences in the utilization of services (i.e., coaching sessions, pharmacotherapy) and tobacco cessation among callers to the Arizona Smokers' Helpline (ASHLine). The study sample included callers enrolled in ASHLine between January 2011 and June 2016. We tracked number of completed coaching sessions. At the 7-month follow-up, callers retrospectively reported use of cessation pharmacotherapy (gum, patch, or lozenge), as well as current tobacco use. Associations between gender and tobacco cessation were tested using logistic regression models. At month 7, 36.4% of women (3,277/9,004) and 40.3% of men (2,960/7,341) self-reported 30-day point prevalence abstinence. Compared to men, fewer women reported using pharmacotherapy (women: 71.4% vs. men: 73.6%, p = .01) and completed at least five coaching sessions (women: 35.1% vs. men: 38.5%, p < .01). After adjusting for baseline characteristics, women had significantly lower odds of reporting tobacco cessation than men (OR = 0.91, 95% CI: 0.84 to 0.99). However, after further adjustment for use of pharmacotherapy and coaching, there was no longer a significant relationship between gender and tobacco cessation (OR: 0.96, 95% CI: 0.87 to 1.06). Fewer women than men reported tobacco cessation. Women also had lower utilization of quitline cessation services. Although the magnitude of these differences were small, future research on improving the utilization of quitline services among women may be worth pursuing given the large-scale effects of tobacco.
- Yuan, N. P., Nair, U. S., Crane, T. E., Krupski, L., Collins, B. N., & Bell, M. L. (2019). Impact of changes in home smoking bans on tobacco cessation among quitline callers. Health education research, 34(3), 345-355.
- Yuan, N. P., Schultz, J. L., Nair, U. S., & Bell, M. L. (2019). Predictors of Tobacco Cessation Among American Indian/Alaska Native Adults Enrolled in a State Quitline. Substance use & misuse, 1-8.
- Zordan, R. D., Bell, M. L., Price, M., Remedios, C., Lobb, E., Hall, C., & Hudson, P. (2019). Long-term prevalence and predictors of prolonged grief disorder amongst bereaved cancer caregivers: A cohort study. Palliative & supportive care, 1-8.
- Allen, A. M., Yuan, N. P., Wertheim, B. C., Krupski, L., Bell, M. L., & Nair, U. (2018). Gender differences in utilization of services and tobacco cessation outcomes at a state quitline. Translational behavioral medicine.
- Barrett, E., Carr, D., Bell, M. L., & Pogreba-Brown, K. (2018). Post-infectious sequelae after Campylobacter enteric infection: a pilot study in Maricopa County, Arizona, USA. Pilot and feasibility studies, 4(1), 142.
- Bell, M. L. (2018). New guidance to improve sample size calculations for trials: eliciting the target difference. Trials, 19(1), 605.
- Bell, M. L., Dhillon, H. M., Bray, V. J., & Vardy, J. L. (2018). Important differences and meaningful changes for the Functional Assessment of Cancer Therapy-Cognitive Function (FACT-Cog). Journal of patient-reported outcomes, 2(1), 48.
- Bell, M. L., Horton, N. J., Dhillon, H. M., Bray, V. J., & Vardy, J. (2018). Using generalized estimating equations and extensions in randomized trials with missing longitudinal patient reported outcome data. PsychoâOncology.
- Brady, B. R., O'connor, P. A., Nair, U. S., Brady, B. R., & Bell, M. L. (2018). Factors Predicting Client Re-Enrollment in Tobacco Cessation Services in a State Quitline.. Preventing chronic disease, 15(10), E126. doi:10.5888/pcd15.180144More infoQuitlines are an integral part of tobacco treatment programs and reach groups of smokers who have a wide range of barriers to cessation. Although tobacco dependence is chronic and relapsing, little research exists on factors that predict the likelihood of clients re-engaging and reconnecting with quitlines for treatment. The objective of this study was to describe factors that predict the re-enrollment of clients in Arizona's state quitline..This was a retrospective analysis of data collected from clients (N = 49,284) enrolled in the Arizona Smokers' Helpline from January 2011 through June 2016. We used logistic regression to analyze predictors of re-enrollment in services after controlling for theoretically relevant baseline variables (eg, nicotine dependence, smokers in the home) and follow-up variables (eg, program use, quit outcome)..Compared with clients who reported being quit after their first enrollment, clients who reported not being quit were almost 3 times as likely to re-enroll (odds ratio = 2.89; 95% confidence interval, 2.54-3.30). Other predictors were having a chronic condition or a mental health condition, greater nicotine dependence, and lower levels of social support. Women and clients not having other smokers in the home were more likely to re-enroll than were men and clients not living with other smokers..Understanding baseline and in-program factors that predict client-initiated re-enrollment can help quitlines tailor strategies to proactively re-engage clients who may have difficulty maintaining long-term abstinence.
- Carvajal, S. C., Huang, S., Bell, M. L., Denman, C., Guernsey, d., Cornejo, E., Chang, J., Staten, L. K., & Rosales, C. (2018). Behavioral and subjective health changes in US and Mexico border residing participants in two promotora-led chronic disease preventive interventions. Health Education Research.
- Garcia, D. O., Morrill, K. E., Aceves, B., Valdez, L. A., Rabe, B. A., Bell, M. L., Hakim, I. A., Martinez, J. A., & Thomson, C. A. (2018). Feasibility and acceptability of a beverage intervention for Hispanic adults: results from a pilot randomized controlled trial. Public health nutrition, 1-11.
- Garcia, D. O., Valdez, L. A., Bell, M. L., Humphrey, K., Hingle, M. D., McEwen, M. M., & Hooker, S. P. (2018). A Gender- and Culturally-Sensitive Weight Loss Intervention for Hispanic Males: The ANIMO Randomized Controlled Trial Study Protocol and Recruitment Methods. Contemporary Clinical Trials Communications.
- Gordon, J. S., Povis, G., Nair, U. S., Gordon, J. S., Giacobbi, P. R., Bell, M. L., & Armin, J. (2018). Development of a guided imagery tobacco cessation intervention to be delivered by quitline and website. Tobacco Induced Diseases, 16(1). doi:10.18332/tid/83795
- Huang, S., Hu, C., Bell, M. L., Billheimer, D. D., Guerra, S., Roe, D., Vasquez, M., & Bedrick, E. J. (2018). Regularized continuous-time Markov model via elastic net. Biometrics.
- Huang, S., Hu, C., Bell, M. L., Billheimer, D., Guerra, S., Roe, D., Vasquez, M. M., & Bedrick, E. J. (2018). Regularized continuous‐time Markov Model via elastic net. Biometrics, 74(3), 1045-1054.
- Johnson, S. B., Butow, P. N., Bell, M. L., Detering, K., Clayton, J. M., Silvester, W., Kiely, B. E., Clarke, S., Vaccaro, L., & Stockler, M. R. (2018). A randomised controlled trial of an advance care planning intervention for patients with incurable cancer. British journal of cancer, 1.
- Lent, A. B., OâConnor, P. A., Reikowsky, R. C., Nair, U. S., & Bell, M. L. (2018). Quit outcomes among clients ineligible for cessation medication through the state quitline: a retrospective, observational study. BMC public health, 18(1), 1001.
- Morrill, K. E., Aceves, B., Valdez, L. A., Thomson, C. A., Hakim, I. A., Bell, M. L., Martinez, J. A., & Garcia, D. O. (2017). Feasibility and Acceptability of a Beverage Intervention for Hispanic Adults: A Protocol for a Pilot Randomized Controlled Trial. Nutrition Journal.
- Morrill, K. E., Aceves, B., Valdez, L. A., Thomson, C. A., Hakim, I. A., Bell, M. L., Martinez, J. A., & Garcia, D. O. (2018). Feasibility and acceptability of a beverage intervention for Hispanic adults: a protocol for a pilot randomized controlled trial. Nutrition journal, 17(1), 16.
- Nair, U. S., Bell, M. L., Yuan, N. P., Wertheim, B. C., & Thomson, C. A. (2017). Associations between comorbid health conditions and quit outcomes among smokers enrolled in a state quitline, Arizona, 2011-2016.. Public Health Reports.
- Pogreba-Brown, K., O'Connor, P., Matthews, J., Barrett, E., & Bell, M. L. (2018). Caseâcase analysis of Campylobacter and Salmonellaâusing surveillance data for outbreak investigations and monitoring routine risk factors. Epidemiology & Infection, 146(15), 1916-1921.
- Rabe, B. A., Day, S., Fiero, M. H., & Bell, M. L. (2018). Missing data handling in nonâinferiority and equivalence trials: A systematic review. Pharmaceutical Statistics.
- Sharpe, L., Thewes, B., Turner, J., Gilchrist, J., Fardell, J. E., Girgis, A., Tesson, S., Descallar, J., Bell, M. L., & Beith, J. (2018). Medical, demographic and psychological correlates of fear of cancer recurrence (FCR) morbidity in breast, colorectal and melanoma cancer survivors with probable clinically significant FCR seeking psychological treatment through the ConquerFear study. Supportive Care in Cancer, 1-10.
- Tattersall, M. H., Kerridge, I., Johnson, S. B., Butow, P. N., & Bell, M. L. (2018). How Well Do Current Measures Assess the Impact of Advance Care Planning on Concordance Between Patient Preferences for End-of-Life Care and the Care Received: A Methodological Review.. Journal of pain and symptom management, 55(2), 480-495. doi:10.1016/j.jpainsymman.2017.09.008More infoResearch has begun to focus on whether Advance Care Planning (ACP) has the capacity to influence care, and to examine whether ACP can be effective in meeting patients' wishes at the end of their lives. Little attention has been paid, however, to the validity and clinical relevance of existing measures..A search of Medline and CINHAL identified ACP studies measuring concordance between end-of-life (EoL) preferences and the care received. Databases were searched from 2000 to August 2016. We developed a checklist to evaluate the quality of included studies. Data were collected on the proportion of patients who received concordant care, extracted from manuscript tables or calculated from the text..Of 2941 papers initially identified, nine eligible studies were included. Proportions of patients who received concordant care varied from 14% to 98%. Studies were heterogeneous and methodologically poor, with limited attention paid to bias/external validity. Studies varied with regards to design of measures, the meaning of relevant terms like "preference" "EoL care" and "concordance," and the completeness of reported data..Methodological variations and weaknesses compromise the validity of study results, and prevent meaningful comparisons between studies or synthesis of the results. Effectively evaluating whether ACP interventions enhance a patient's capacity to receive the care they want requires harmonization of research. This demands standardization of methods across studies, validating of instruments, and consensus based on a consistent conceptual framework regarding what constitutes a meaningful outcome measure.
- Valdez, L. A., Aceves, B., Mcewen, M. M., Valdez, L. A., Mcewen, M. M., Loya, J. C., Humphrey, K., Hooker, S. P., Hingle, M., Garcia, D. O., Campas, D., Bell, M. L., & Aceves, B. (2018). The Feasibility of a Gender- and Culturally-Sensitive Weight Loss Intervention Plus Mobile Health Technology for Hispanic Males: 642 Board #2 May 30 3 15 PM - 5 15 PM. Medicine and Science in Sports and Exercise, 50(5S), 135. doi:10.1249/01.mss.0000535530.82900.03
- Valdez, L. A., Valdez, L. A., Rabe, B. A., Loya, J. C., Hooker, S. P., Garcia, D. O., & Bell, M. L. (2018). Associations Between Self-Efficacy and Acculturation on Leisure-Time Physical Activity in Hispanic Men Enrolled in a Weight Loss Intervention: 887 Board #148 May 30 3 30 PM - 5 00 PM. Medicine and Science in Sports and Exercise, 50(5S), 203. doi:10.1249/01.mss.0000535752.48574.84
- Whitehead, A. L., Julious, S. A., & Bell, M. L. (2018). Guidance for using pilot studies to inform the design of intervention trials with continuous outcomes.. Clinical epidemiology, 10, 153-157. doi:10.2147/clep.s146397More infoA pilot study can be an important step in the assessment of an intervention by providing information to design the future definitive trial. Pilot studies can be used to estimate the recruitment and retention rates and population variance and to provide preliminary evidence of efficacy potential. However, estimation is poor because pilot studies are small, so sensitivity analyses for the main trial's sample size calculations should be undertaken..We demonstrate how to carry out easy-to-perform sensitivity analysis for designing trials based on pilot data using an example. Furthermore, we introduce rules of thumb for the size of the pilot study so that the overall sample size, for both pilot and main trials, is minimized..The example illustrates how sample size estimates for the main trial can alter dramatically by plausibly varying assumptions. Required sample size for 90% power varied from 392 to 692 depending on assumptions. Some scenarios were not feasible based on the pilot study recruitment and retention rates..Pilot studies can be used to help design the main trial, but caution should be exercised. We recommend the use of sensitivity analyses to assess the robustness of the design assumptions for a main trial.
- Yuan, N. P., Yuan, N. P., Wertheim, B. C., Thomson, C. A., Nair, U. S., & Bell, M. L. (2018). Associations Between Comorbid Health Conditions and Quit Outcomes Among Smokers Enrolled in a State Quitline, Arizona, 2011-2016.. Public health reports (Washington, D.C. : 1974), 133(2), 200-206. doi:10.1177/0033354918764903More infoSmokers with comorbid health conditions have a disproportionate burden of tobacco-related death and disease. A better understanding of differences in quit rates among smokers with comorbid health conditions can guide tailoring of quitline services for subgroups. The objective of this study was to examine self-reported tobacco cessation rates among Arizona Smokers' Helpline callers with chronic health conditions (CHCs) and/or a mental health condition (MHC)..We analyzed data from quitline telephone callers (n = 39 779) who enrolled in and completed at least 1 behavioral counseling session (ie, coaching call). We categorized callers as CHC only (cardiovascular disease/respiratory-related/cancer; 32%), MHC only (eg, mood/anxiety/substance dependence; 13%), CHC + MHC (25%), or no comorbid condition (30%). We assessed 30-day abstinence at 7-month follow-up for 16 683 clients (41.9%). We used logistic regression analysis to test associations between comorbidity and quit outcomes after controlling for relevant variables (eg, nicotine dependence)..Overall quit rates were 45.4% for those with no comorbid condition, 43.3% for those with a CHC only, 37.0% for those with an MHC only, and 33.3% for those with CHC + MHC. Compared with other groups, the CHC + MHC group had the lowest odds of quitting (adjusted odds ratio = 0.60; 95% confidence interval, 0.52-0.69)..Having a comorbid condition was associated with lower quit rates, and smokers with co-occurring CHCs and MHCs had the lowest quit rates. Quitlines should evaluate more intensive, evidence-driven, tailored services for smoking cessation among callers with comorbid conditions.
- Zapien, J. G., Vucovich, E. C., Vasquez, M. D., Valenica, C., Sabo, S., Rosales, C. B., Ingram, M., Gonzalez-fagoaga, E., Champion, C. D., & Bell, M. L. (2018). Meta Salud Diabetes study protocol: a cluster-randomised trial to reduce cardiovascular risk among a diabetic population of Mexico.. BMJ open, 8(3), e020762. doi:10.1136/bmjopen-2017-020762More infoNorthern Mexico has among the highest rates of cardiovascular disease (CVD) and diabetes in the world. This research addresses core gaps in implementation science to develop, test and scale-up CVD risk-reduction interventions in diabetics through a national primary care health system..The Meta Salud Diabetes (MSD) research project is a parallel two-arm cluster-randomised clinical behavioural trial based in 22 (n=22) health centres in Sonora, Mexico. MSD aims to evaluate the effectiveness of the MSD intervention for the secondary prevention of CVD risk factors among a diabetic population (n=320) compared with the study control of usual care. The MSD intervention consists of 2-hour class sessions delivered over a 13-week period providing educational information to encourage sustainable behavioural change to prevent disease complications including the adoption of physical activity. MSD is delivered within the context of Mexico's national primary care health centre system by health professionals, including nurses, physicians and community health workers via existing social support groups for individuals diagnosed with chronic disease. Mixed models are used to estimate the effect of MSD by comparing cardiovascular risk, as measured by the Framingham Risk Score, between the trial arms. Secondary outcomes include hypertension, behavioural risk factors and psychosocial factors..This work is supported by the National Institutes of Health, National Heart Lung and Blood Institute (1R01HL125996-01) and approved by the University of Arizona Research Institutional Review Board (Protocol 1508040144) and the Research Bioethics Committee at the University of Sonora. The first Internal Review Board approval date was 31 August 2015 with five subsequent approved amendments. This article refers to protocol V.0.2, dated 30 January 2017. Results will be disseminated via peer-reviewed publication and presentation at international conferences and will be shared through meetings with health systems officials..NCT0280469; Pre-results.
- Bell, M. L. (2017). Challenges to interpreting patient reported outcomes in clinical trials: author rejoinder. Annals of translational medicine, 5(21).
- Bell, M. L., Fiero, M. H., Dhillon, H. M., Bray, V. J., & Vardy, J. L. (2017). Statistical Controversies in Cancer Research: Using standardized effect size graphs to enhance interpretability of cancer-related clinical trials with patient reported outcomes. Annals of Oncology.
- Butow, P. N., Turner, J., Gilchrist, J., Sharpe, L., Smith, A. B., Fardell, J. E., Tesson, S., O’Connell, R., Girgis, A., Gebski, V. J., & others, . (2017). Randomized Trial of ConquerFear: A Novel, Theoretically Based Psychosocial Intervention for Fear of Cancer Recurrence. Journal of Clinical Oncology, 35(36), 4066--4077.
- Carvajal, S. C., Huang, S., Zapien, J. G., Staten, L. K., Rosales, C., Huang, S., Denman, C. A., Cornejo, E., Chang, J., Carvajal, S. C., & Bell, M. L. (2017). Health behavior changes in Latino US-Mexico border residing adults participating in chronic disease preventive interventions. The European health psychologist, 19.More infoBackground: Non-communicable diseases are the leading cause of death among Mexican-origin adults. There is growing evidence for the effectiveness of community health worker led group interventions in lowering risk. This study aims to examine the behavioral and perceived health impacts of one such intervention tested in a US border community--Pasos Adelante, and contrasts those findings with those of its Northern Mexico adapted and delivered intervention, Meta Salud. The former is a Centers for Disease Control disseminated intervention based on its clinical impact, but little is known about which behavioral change objectives have been successfully addressed. Methods: The primary data comes from the largest cohort to date for evaluating Pasos (N =347); participants were recruited from community and clinical settings. Pasos was developed from a social cognitive theory-based intervention with extensive adaptations based on community participatory methods. Questionnaire data at baseline, conclusion of program, and at 6-month post program initiation were analyzed (e.g., generalized linear logistic mixed models). Findings: Pasos participants reported more physical activity (e.g., meeting CDC guidelines), healthier dietary choices and more positive perceived health at both post program assessments. Across both interventions, participants showed improved indicators of physical activity, whole milk consumption, sugary drink consumption, fruit consumption, mental health and self-rated health (ps
- Dhillon, H. M., Bell, M. L., Ploeg, H. P., Turner, J. D., Kabourakis, M., Spencer, L., Lewis, C., Hui, R., Blinman, P., Clarke, S. J., & others, . (2017). Impact of Physical Activity on Fatigue and Quality of Life in People with Advanced Lung Cancer: a Randomised Controlled Trial. Annals of Oncology, mdx205.
- Ernst, K. C., Erly, S., Adusei, C., Bell, M. L., Kessie, D. K., Biritwum-Nyarko, A., & Ehiri, J. (2017). Reported bed net ownership and use in social contacts is associated with uptake of bed nets for malaria prevention in pregnant women in Ghana. Malaria journal, 16(1), 13.
- Fiero, M. H., Hsu, C., & Bell, M. L. (2017). A pattern-mixture model approach for handling missing continuous outcome data in longitudinal cluster randomized trials. Statistics in medicine, 36(26), 4094--4105.
- Fiero, M. H., Yip, D., Vardy, J. L., Price, M. A., Kabourakis, M., Fiero, M. H., Dhillon, H. M., Bray, V. J., Boyle, F. M., & Bell, M. L. (2017). Evaluation of a Web-Based Cognitive Rehabilitation Program in Cancer Survivors Reporting Cognitive Symptoms After Chemotherapy.. Journal of clinical oncology, 35(2), 217-225. doi:10.1200/jco.2016.67.8201More infoPurpose Cognitive impairment is reported frequently by cancer survivors. There are no proven treatments. We evaluated a cognitive rehabilitation program (Insight) and compared it with standard care in cancer survivors self-reporting cognitive symptoms. Patients and Methods We recruited adult cancer survivors with a primary malignancy (excluding central nervous system malignancies) who had completed three or more cycles of adjuvant chemotherapy in the previous 6 to 60 months and reported persistent cognitive symptoms. All participants received a 30-minute telephone consultation and were then randomly assigned to the 15-week, home-based intervention or to standard care. Primary outcome was self-reported cognitive function (Functional Assessment of Cancer Therapy Cognitive Function [FACT-COG] perceived cognitive impairment [PCI] subscale): difference between groups after intervention (T2) and 6 months later (T3). Results A total of 242 participants were randomly assigned: median age, 53 years; 95% female. The primary outcome of difference in FACT-COG PCI was significant, with less PCI in the intervention group at T2 ( P < .001). This difference was sustained at T3 ( P < .001). At T2, there was a significant difference in all FACT-COG subscales, favoring the intervention. Neuropsychological results were not significantly different between the groups at T2 or T3. There were significantly lower levels of anxiety/depression and fatigue in the intervention group at T2. There were significant improvements in stress in the intervention group at both time points. There was no significant difference in quality of life between the groups at T2, but the intervention group had better quality of life at T3. Conclusion The intervention, Insight, led to improvements in cognitive symptoms compared with standard care. To our knowledge, this is the first large randomized controlled trial showing an improvement in self-reported cognitive function in cancer survivors, indicating that this intervention is a feasible treatment.
- Halpern, M. T., Fiero, M. H., & Bell, M. L. (2017). Impact of caregiver activities and social supports on multidimensional caregiver burden: analyses from nationally-representative surveys of cancer patients and their caregivers. Quality of Life Research, 26(6), 1587--1595.
- Hyatt, A., Lipson-Smith, R., Schofield, P., Gough, K., Sze, M., Aldridge, L., Goldstein, D., Jefford, M., Bell, M. L., & Butow, P. (2017). Communication challenges experienced by migrants with cancer: A comparison of migrant and English-speaking Australian-born cancer patients. Health Expectations.
- Hyatt, A., Lipson-Smith, R., Schofield, P., Gough, K., Sze, M., Goldstein, L., Jefford, M., Bell, M. L., & Butow, P. (2016). Communication challenges experienced by migrants with cancer: a comparison of migrant and English-speaking Australian-born cancer patients. Health Expectations.
- Ingram, M., Doubleday, K., Bell, M. L., Lohr, A., Murrieta, L., Velasco, M., Blackburn, J., Sabo, S., Zapien, J., & Carvajal, S. C. (2017). Community health worker impact on chronic disease outcomes within primary care examined using electronic health records. American journal of public health, 107(10), 1668--1674.
- Johnson, S. B., Butow, P. N., Kerridge, I., Bell, M. L., & Tattersall, M. (2017). How well do current measures assess the impact of advance care planning on concordance between patient preferences for end of life care and the care received: A methodological review. Journal of pain and symptom management.
- Jung, A. M., Schweers, N., Bell, M. L., Nair, U., & Yuan, N. P. (2017). Peer Reviewed: Tobacco Use Cessation Among Quitline Callers Who Implemented Complete Home Smoking Bans During the Quitting Process. Preventing chronic disease, 14.
- Mercieca-Bebber, R. L., Price, M. A., Bell, M. L., King, M. T., Webb, P. M., & Butow, P. N. (2017). Ovarian cancer study dropouts had worse health-related quality of life and psychosocial symptoms at baseline and over time. Asia-Pacific Journal of Clinical Oncology, 13(5).
- Olivier, J., May, W. L., & Bell, M. L. (2017). Relative effect sizes for measures of risk. Communications in Statistics-Theory and Methods, 46(14), 6774--6781.
- Oren, E., Bell, M. L., Garcia, F., Perez-Velez, C., & Gerald, L. B. (2017). Promoting adherence to treatment for latent TB infection through mobile phone text messaging: study protocol for a pilot randomized controlled trial. Pilot and Feasibility Studies, 3(1), 15.
- Sabo, S., Flores, M., Wennerstrom, A., Bell, M. L., Verdugo, L., Carvajal, S., & Ingram, M. (2017). Community Health Workers Promote Civic Engagement and Organizational Capacity to Impact Policy. Journal of Community Health, 1--7.
- Schmidt, C. A., Romine, J. K., Bell, M. L., Armin, J., & Gordon, J. S. (2017). User Participation and Engagement With the See Me Smoke-Free mHealth App: Prospective Feasibility Trial. JMIR mHealth and uHealth, 5(10).
- Ashbeck, E. L., & Bell, M. L. (2016). Single time point comparisons in longitudinal randomized controlled trials: power and bias in the presence of missing data. BMC medical research methodology, 16(1), 43.
- Bell, M. L., Fairclough, D. L., Fiero, M. H., & Butow, P. N. (2016). Handling missing items in the Hospital Anxiety and Depression Scale (HADS): a simulation study. BMC research notes, 9(1), 479.
- Bray, V. J., Dhillon, H. M., Bell, M. L., Kabourakis, M., Fiero, M. H., Yip, D., Boyle, F., Price, M. A., & Vardy, J. L. (2016). Evaluation of a Web-Based Cognitive Rehabilitation Program in Cancer Survivors Reporting Cognitive Symptoms After Chemotherapy. Journal of Clinical Oncology, 35(2), 217-225.
- Fiero, M. H., Huang, S., Oren, E., & Bell, M. L. (2016). Statistical analysis and handling of missing data in cluster randomized trials: a systematic review. Trials, 17(1), 72.
- Huang, S., Fiero, M. H., & Bell, M. L. (2016). Generalized estimating equations in cluster randomized trials with a small number of clusters: Review of practice and simulation study. Clinical Trials, 13(4), 445-449.
- Johnson, S., Clayton, J., Butow, P. N., Silvester, W., Detering, K., Hall, J., Kiely, B. E., Cebon, J., Clarke, S., & Bell, M. L. (2016). Advance care planning in patients with incurable cancer: study protocol for a randomised controlled trial. BMJ open, 6(12), e012387.
- Mercieca‐Bebber, R. L., Price, M. A., Bell, M. L., King, M. T., Webb, P. M., & Butow, P. N. (2016). Ovarian cancer study dropouts had worse health‐related quality of life and psychosocial symptoms at baseline and over time. Asia‐Pacific Journal of Clinical Oncology.
- Muramoto, M. L., Gordon, J. S., Bell, M. L., Nichter, M., Floden, L., Howerter, A., & Ritenbaugh, C. K. (2016). Tobacco cessation training for complementary and alternative medicine practitioners: Results of a practice-based trial. American journal of preventive medicine, 51(2), e35-e44.
- Muramoto, M. L., Gordon, J. S., Bell, M. L., Nichter, M., Floden, L., Howerter, A., Ritenbaugh, C., Muramoto, M. L., Gordon, J. S., Bell, M. L., Nichter, M., Floden, L., Howerter, A., & Ritenbaugh, C. (2016). Tobacco Cessation Training for Complementary and Alternative Medicine Practitioners: Results of a Practice-Based Trial.. American journal of preventive medicine.
- Olivier, J., May, W. L., & Bell, M. L. (2016). Relative Effect Sizes for Measures of Risk. Communications in Statistics-Theory and Methods, 00-00.
- Price, M. A., Butow, P. N., Bell, M. L., Friedlander, M., Fardell, J. E., Protani, M. M., & Webb, P. M. (2016). Helplessness/hopelessness, minimization and optimism predict survival in women with invasive ovarian cancer: a role for targeted support during initial treatment decision-making?. Supportive Care in Cancer, 24(6), 2627-2634.
- Valdez, L. A., Bell, M. L., & Garcia, D. O. (2016). Assessing the influence of living and working conditions on alcohol consumption on agricultural workers in Mexico: a cross sectional study using the Encuesta Nacional de Jornaleros 2010 survey. Californian Journal of Health Promotion, 14(3), 12-21.
- Wratten, C., Wratten, C., Thomson, V., Tang, C. I., Poulsen, M. G., Porceddu, S. V., Penniment, M. G., Morton, R. P., Milross, C. G., Macann, A. M., Krawitz, H., King, M. T., Hockey, H. U., Fua, T., Fraser-browne, C. L., & Bell, M. L. (2016). Influence of domiciliary humidification on symptom burden and feeding tube use up to 2 years postradiation therapy for head and neck cancer: Trans-Tasman Radiation Oncology Group (TROG) 07.03 RadioHUM randomized phase 2 trial secondary analysis. International Journal of Radiation Oncology Biology Physics, 96(2), S217-S218. doi:10.1016/j.ijrobp.2016.06.540
- Denman, C. A., Bell, M. L., Cornejo, E., Zapien, J. G., Carvajal, S., & Rosales, C. (2015). Changes in health behaviors and self-rated health of participants in Meta Salud: a primary prevention intervention of NCD in Mexico. Global heart, 10(1), 55--61.
- Dodds, S. E., Pace, T. W., Bell, M. L., Fiero, M., Negi, L. T., Raison, C. L., & Weihs, K. L. (2015). Feasibility of Cognitively-Based Compassion Training (CBCT) for breast cancer survivors: a randomized, wait list controlled pilot study. Supportive Care in Cancer, 23(12), 3599--3608.
- Fiero, M., Huang, S., & Bell, M. L. (2015). Statistical analysis and handling of missing data in cluster randomised trials: protocol for a systematic review. BMJ open, 5(5), e007378.
- McDonald, F. E., Patterson, P., White, K. J., Butow, P., & Bell, M. L. (2015). Predictors of unmet needs and psychological distress in adolescent and young adult siblings of people diagnosed with cancer. Psycho-Oncology, 24(3), 333--340.
- S, S., A, W., D, P., C, H., F, R., ML, B., & M., I. (2015). Community Health Worker Professional Advocacy: Voices of Action from the 2014 National Community Health Worker Advocacy Survey. Journal of Ambulatory Care Management, 38(3), 225--35.
- Smith, A., Thewes, B., Turner, J., Gilchrist, J., Fardell, J., Sharpe, L., Bell, M. L., Girgis, A., Grier, M., Byrne, D., & others, . (2015). Pilot of a theoretically grounded psychologist-delivered intervention for fear of cancer recurrence (Conquer Fear). Psycho-Oncology.
- Sze, M., Butow, P., Bell, M., Vaccaro, L., Dong, S., Eisenbruch, M., Jefford, M., Girgis, A., King, M., McGrane, J., & others, . (2015). Migrant Health in Cancer: Outcome Disparities and the Determinant Role of Migrant-Specific Variables. The oncologist, theoncologist--2014.
- Bell, M. L., Fiero, M., Horton, N. J., & Hsu, C. (2014). Handling missing data in RCTs; a review of the top medical journals. BMC medical research methodology, 14(1), 118.
- Bell, M. L., King, M. T., & Fairclough, D. L. (2014). Bias in Area Under the Curve for Longitudinal Clinical Trials With Missing Patient Reported Outcome Data Summary Measures Versus Summary Statistics. SAGE Open, 4(2), 2158244014534858.
- Bell, M. L., Teixeira-Pinto, A., McKenzie, J. E., & Olivier, J. (2014). A myriad of methods: Calculated sample size for two proportions was dependent on the choice of sample size formula and software. Journal of clinical epidemiology, 67(5), 601--605.
- Bell, M., & Fairclough, D. (2014). Practical and statistical issues in missing data for longitudinal patient reported outcomes. Statistical Methods in Medical Research, 23(5), 440-459.
- Butow, P. N., Price, M. A., Bell, M. L., Webb, P. M., deFazio, A., Friedlander, M., Group, A. O., Investigators, L. S., & others, . (2014). Caring for women with ovarian cancer in the last year of life: A longitudinal study of caregiver quality of life, distress and unmet needs. Gynecologic oncology, 132(3), 690--697.
- Denman, C. A., Rosales, C., Cornejo, E., Bell, M. L., Mungu\'\ia, D., Zepeda, T., Carvajal, S., & Zapien, J. G. (2014). Evaluation of the Community-Based Chronic Disease Prevention Program Meta Salud in Northern Mexico, 2011--2012. Preventing chronic disease, 11.
- Goldstein, D., Bell, M., Butow, P., Sze, M., Vaccaro, L., Dong, S., Liauw, W., Hui, R., Tattersall, M., Ng, W., & others, . (2014). Immigrants' perceptions of the quality of their cancer care--An Australian comparative study, identifying potentially modifiable factors. Annals of Oncology, mdu182.
- Hodson, L., Eyles, H. C., McLachlan, K. J., Bell, M. L., Green, T. J., & Skeaff, C. M. (2014). Plasma and Erythrocyte Fatty Acids Reflect Intakes of Saturated and n--6 PUFA within a Similar Time Frame. The Journal of nutrition, 144(1), 33--41.
- Juraskova, I., Butow, P., Bonner, C., Bell, M., Smith, A., Seccombe, M., Boyle, F., Reaby, L., Cuzick, J., & Forbes, J. (2014). Improving decision making about clinical trial participation--a randomised controlled trial of a decision aid for women considering participation in the IBIS-II breast cancer prevention trial. British Journal of Cancer.
- King, M. T., Bell, M. L., Costa, D., Butow, P., & Oh, B. (2014). The Quality of Life Questionnaire Core 30 (QLQ-C30) and Functional Assessment of Cancer-General (FACT-G) differ in responsiveness, relative efficiency, and therefore required sample size. Journal of Clinical Epidemiology, 67(1), 100--107.
- Macann, A., Fua, T., Milross, C. G., Porceddu, S. V., Penniment, M., Wratten, C., Krawitz, H., Poulsen, M., Tang, C. I., Morton, R. P., & others, . (2014). Phase 3 Trial of Domiciliary Humidification to Mitigate Acute Mucosal Toxicity During Radiation Therapy for Head-and-Neck Cancer: First Report of Trans Tasman Radiation Oncology Group (TROG) 07.03 RadioHUM Study. International Journal of Radiation Oncology* Biology* Physics, 88(3), 572--579.
- McDonald, F., Patterson, P., White, K., Butow, P., & Bell, M. (2014). Predictors of unmet needs and psychological distress in adolescent and young adult siblings of people diagnosed with cancer. Psycho-Oncology.
- Patterson, P., McDonald, F., Butow, P., White, K., Costa, D., Millar, B., Bell, M., Wakefield, C., & Cohn, R. (2014). Psychometric evaluation of the Sibling Cancer Needs Instrument (SCNI): an instrument to assess the psychosocial unmet needs of young people who are siblings of cancer patients. Supportive Care in Cancer, 22(3), 653--665.
- Ralph, A. F., Ager, B., Bell, M. L., Collins, I. M., Andrews, L., Tucker, K., Nicole, O., Phillips, K., Butow, P., & others, . (2014). Women's preferences for selective estrogen reuptake modulators: an investigation using the time trade off technique. SpringerPlus, 3(1), 264.
- Ralph, A. F., Ager, B., Bell, M. L., Collins, I. M., Andrews, L., Tucker, K., Phillips, K., & Butow, P. (2014). Women's preferences for selective estrogen reuptake modulators: An investigation using protection motivation theory. Patient education and counseling.
- Bell, M. L., Butow, P. N., & Goldstein, D. (2013). Informatively missing quality of life and unmet needs sex data for immigrant and Anglo-Australian cancer patients and survivors. Quality of Life Research, 1-4.
- Bell, M. L., Kenward, H. G., Fairclough, D. L., & Horton, N. J. (2013). Differential dropout and bias in randomised controlled trials: when it matters and when it may not. BMJ, 346:e8668.
- Butow, P. N., Aldridge, L., Bell, M. L., Sze, M., Eisenbruch, M., Jefford, M., Schofield, P., Girgis, A., King, M., & Duggal-Beri, P. (2013). Inferior health-related quality of life and psychological well-being in immigrant cancer survivors: A population-based study. European Journal of Cancer.
- Butow, P. N., Bell, M. L., Smith, A. B., Fardell, J. E., Thewes, B., Turner, J., Gilchrist, J., Beith, J., Girgis, A., & Sharpe, L. (2013). Conquer fear: protocol of a randomised controlled trial of a psychological intervention to reduce fear of cancer recurrence. Psycho-Oncology, 13, 201.
- Butow, P. N., Sze, M., Eisenbruch, M., Bell, M. L., Aldridge, L. J., Abdo, S., Tanious, M., Dong, S., Iedema, R., & Vardy, J. (2013). Should culture affect practice? A comparison of prognostic discussions in consultations with immigrant versus native-born cancer patients. Patient Education and Counseling.
- Butow, P., Bell, M., Aldridge, L., Sze, M., Eisenbruch, M., Jefford, M., Schofield, P., Girgis, A., King, M., & Duggal, P. (2013). Unmet needs in immigrant cancer survivors: a cross-sectional population-based study. Supportive Care in Cancer, 1-12.
- Olivier, J., & Bell, M. L. (2013). Effect Sizes for 2× 2 Contingency Tables. PLOS One, 8, e58777.
- Olivier, J., & Bell, M. L. (2013). The Importance of Statistics in Cancer Research. World Journal of Cancer Research, 1, 78-81.
- Olivier, J., King, M. T., & Bell, M. L. (2013). Scientific rigour in psycho-oncology trials: why and how to avoid common statistical errors.. Psycho-oncology, 22(3), 499-505. doi:10.1002/pon.3046More infoIt is well documented that statistical and methodological flaws are common in much of the health research literature, including psycho-oncology. These can have far-reaching effects, including the publishing of misleading results; the wasting of time, effort, and financial resources; exposure of patients to the potential harms of research and decreased confidence in science and researchers by the public..Several of the most common statistical errors and methodological pitfalls that occur in the field of psycho-oncology are discussed, including those that occur at the design, analysis, reporting and conclusion stages..Fourteen topics are briefly discussed, explaining why there is a problem and how to avoid it. These include proper approaches to power, clustering, missing data, categorization of continuous variables, subgroup analyses, multiple comparisons, statistical interactions, confidence intervals and correct interpretation of p-values. Extensive referencing points the reader to more in-depth explanations..To increase the scientific rigour in psycho-oncology, researchers should involve a biostatistician from the beginning of the study and should commit to continuing education on best practices in the fields of statistics and reporting.
- Patterson, P., McDonald, F., Butow, P., White, K., Costa, D., Pearce, A., & Bell, M. (2013). Psychometric evaluation of the Offspring Cancer Needs Instrument (OCNI): an instrument to assess the psychosocial unmet needs of young people who have a parent with cancer. Supportive Care in Cancer, 1-12.
- Price, M., Bell, M., Sommeijer, D., Friedlander, M., Stockler, M., Defazio, A., Webb, P., & Butow, P. (2013). Physical symptoms, coping styles and quality of life in recurrent ovarian cancer: A prospective population-based study over the last year of life. Gynecological Oncology.
- Ramrakha, S., Paul, C., Moffitt, T. E., Dickson, N., Caspi, A., & Bell, M. L. (2013). The relationship between multiple sex partners and anxiety, depression, and substance dependence disorders: a cohort study.. Archives of sexual behavior, 42(5), 863-72. doi:10.1007/s10508-012-0053-1More infoChanges in sexual behavior have resulted in longer periods of multiple serial or concurrent relationships. This study investigated the effects of multiple heterosexual partners on mental health, specifically, whether higher numbers of partners were linked to later anxiety, depression, and substance dependency. Data from the Dunedin Multidisciplinary Health and Development Study, a prospective, longitudinal study of a birth cohort born in 1972-1973 in Dunedin, New Zealand were used. The relationship between numbers of sex partners over three age periods (18-20, 21-25, and 26-32 years) and diagnoses of anxiety, depression, and substance dependence disorder at 21, 26, and 32 years were examined, using logistic regression. Interaction by gender was examined. Adjustment was made for prior mental health status. There was no significant association between number of sex partners and later anxiety and depression. Increasing numbers of sex partners were associated with increasing risk of substance dependence disorder at all three ages. The association was stronger for women and remained after adjusting for prior disorder. For women reporting 2.5 or more partners per year, compared to 0-1 partners, the adjusted odd ratios (and 95 % CIs) were 9.6 (4.4-20.9), 7.3 (2.5-21.3), and 17.5 (3.5-88.1) at 21, 26, and 32 years, respectively. Analyses using new cases of these disorders showed similar patterns. This study established a strong association between number of sex partners and later substance disorder, especially for women, which persisted beyond prior substance use and mental health problems more generally. The reasons for this association deserve investigation.
- Stein, R. A., Sharpe, L., Bell, M. L., Boyle, F. M., Dunn, S. M., & Clarke, S. J. (2013). Randomized controlled trial of a structured intervention to facilitate end-of-life decision making in patients with advanced cancer. Journal of Clinical Oncology, 31, 3403-3410.
- Thewes, B., Bell, M., & Butow, P. (2013). Fear of cancer recurrence in young early‐stage breast cancer survivors: the role of metacognitive style and disease‐related factors. Psycho-Oncology.
- Thewes, B., Bell, M., Butow, P., Beith, J., Boyle, F., Friedlander, M., & McLachlan, S. (2013). Psychological morbidity and stress but not social factors influence level of fear of cancer recurrence in young women with early breast cancer: results of a cross‐sectional study. Psycho-Oncology.
- Sharpe, L., Robertson, R., Juraskova, I., Butow, P., Bonner, C., & Bell, M. L. (2012). Quantity vs. quality: an exploration of the predictors of posttreatment sexual adjustment for women affected by early stage cervical and endometrial cancer.. The journal of sexual medicine, 9(11), 2952-60. doi:10.1111/j.1743-6109.2012.02860.xMore infoWomen with early stage cervical and endometrial cancer may experience complex posttreatment changes to their sexual function, but clinical practice and past research have focused more on the quantity than the perceived quality of sexual life..The aims of this prospective study were to explore the following: (i) the relative importance of quantity vs. quality of sexual life over the first year posttreatment; (ii) the psychological and sexual predictors of overall sexual function; and (iii) the relationship between sexual function and quality of life (QoL)..Fifty-three cancer patients completed standardized measures at baseline, with follow-up at 6 and 12 months posttreatment. Analyses were based on prespecified linear mixed models with overall sexual function and QoL as outcomes, and quality and quantity of sexual life, anxiety, and depression as the main predictors of interest. Radiotherapy, age, and relationship satisfaction were controlled for as potential confounders..Derogatis Sexual Functioning Inventory subscales to assess quantity (Drive) and quality (Satisfaction) of sexual life, and overall sexual function (Global Sexual Satisfaction Index); Functional Assessment of Cancer Therapy--General to assess QoL; Hospital Anxiety and Depression Scale to assess psychological distress; and Relationship Satisfaction Interaction Scale to assess relationship satisfaction..The models demonstrated that: (i) overall sexual function was predicted more strongly by the perceived quality than the quantity of sexual interactions, (ii) a small change in perceived quality had a large impact on overall sexual function, and (iii) overall sexual function was a predictor of QoL..This study found that quality rather than quantity of sexual life is the best predictor of overall sexual function among women treated for early stage cervical and endometrial cancer, indicating the importance of including quality indices in posttreatment sexual assessment in clinical practice and research studies.
- Sze, M., Schofield, P., King, M., Jefford, M., Goldstein, D., Eisenbruch, M., Duggal-beri, P., Butow, P. N., Bell, M. L., & Aldridge, L. (2012). Cancer survivorship outcomes in immigrants.. Journal of Clinical Oncology, 30(15_suppl), 6111-6111. doi:10.1200/jco.2012.30.15_suppl.6111More info6111 Background: Immigration is increasing world-wide. Cancer survivorship is now recognised as a period of difficult adjustment for all patients, and possibly more so for immigrants. We explored d...
- Thewes, B., Stuart-harris, R., Grossi, M., Dalley, D., Capp, A., Butow, P., Bell, M. L., & Beith, J. (2012). Fear of cancer recurrence in young women with a history of early-stage breast cancer: a cross-sectional study of prevalence and association with health behaviours.. Supportive care in cancer, 20(11), 2651-9. doi:10.1007/s00520-011-1371-xMore infoFear of cancer recurrence (FCR) is common and associated with younger age. This study aimed to explore the prevalence and correlates of FCR amongst younger survivors of early breast cancer..A total of 218 women aged 18-45 were diagnosed with stage 0-2 breast cancer at least 1 year earlier..The participants completed a web-based survey including a validated measure of FCR and items exploring medical surveillance practices and health care use..A total of 70% of participants reported clinical levels of FCR. Higher FCR was associated with higher frequency of unscheduled visits to the GP, higher frequency of breast self-examination and other forms of self-examination for cancer, not having mammograms or ultrasounds or other forms of cancer screening in the past year, more complementary therapy use and the use of counselling and support groups..Young women with breast cancer are particularly vulnerable to FCR. The present study provides preliminary evidence that FCR is associated with higher health costs and lower surveillance rates which may compromise health outcomes. Routine screening for FCR in follow-up care is recommended.
- Turner, J., Thewes, B., Smith, A. B., Fardell, J. E., Butow, P., & Bell, M. L. (2012). Conquer Fear: The Development And Pilot Testing Of A Novel Psychological Treatment For Fear Of Cancer Recurrence. Asia-pacific Journal of Clinical Oncology, 8. doi:10.1111/ajco.12029
- Vardy, J., Ploeg, H. P., Dhillon, H. M., Clarke, S., Boyer, M., & Bell, M. L. (2012). The impact of physical activity on fatigue and quality of life in lung cancer patients: a randomised controlled trial protocol.. BMC cancer, 12(1), 572. doi:10.1186/1471-2407-12-572More infoPeople with lung cancer have substantial symptom burden and more unmet needs than the general cancer population. Physical activity (PA) has been shown to positively influence quality of life (QOL), fatigue and daily functioning in the curative treatment of people with breast and colorectal cancers and lung diseases, as well as in palliative settings. A randomised controlled trial (RCT) is needed to determine if lung cancer patients benefit from structured PA intervention. The Physical Activity in Lung Cancer (PAL) trial is designed to evaluate the impact of a 2-month PA intervention on fatigue and QOL in patients with non-resectable lung cancer. Biological mechanisms will also be studied..A multi-centre RCT with patients randomised to usual care or a 2-month PA programme, involving supervised PA sessions including a behavioural change component and home-based PA. QOL questionnaires, disease and functional status and body composition will be assessed at baseline, 2, 4 and 6 months follow-up. The primary endpoint is comparative levels of fatigue between the 2 arms. Secondary endpoints include: QOL, functional abilities and physical function. Exploratory endpoints include: anxiety, depression, distress, dyspnoea, PA behaviour, fitness, hospitalisations, survival, cytokines and insulin-like growth factor levels..This study will provide high-level evidence of the effect of PA programmes on cancer-related fatigue and QOL in patients with advanced lung cancer. If positive, the study has the potential to change care for people with cancer using a simple, inexpensive intervention to improve their QOL and help them maintain independent function for as long as possible..Australian New Zealand Clinical Trials Registry No. ACTRN12609000971235.
- Connor, J., Kypri, K., Cousins, K., & Bell, M. L. (2011). P1-414 Aggression between intimate partners in New Zealand: gender differences and alcohol involvement. Journal of Epidemiology and Community Health, 65(Suppl 1), A181-A182. doi:10.1136/jech.2011.142976g.4More infoIntroduction Higher rates of aggression have been described among intimate partners who are heavy drinkers. Drinking at the time of aggressive incidents, and gender differences in the experience of intimate partner aggression in the general population are less well understood. Methods Alcohol consumption, partner9s alcohol consumption, and details of the most severe incident of partner aggression in the past 2 years were reported in a national survey of 18–70 year olds (n=1925). Mean levels of aggression, anger and fear were analysed by gender and alcohol involvement. Multinomial models estimated associations of drinking patterns with aggression to and from the respondent. Results The response rate was 49%. Men and women reported similar prevalence of victimisation and perpetration of aggression (11%–15%). Alcohol was involved in more than a quarter of incidents, and reported more often by women than men, particularly male-only drinking when the respondent was victimised. Women reported more severity, anger and fear accompanying victimisation than men, and these scores differed significantly by involvement of alcohol. Heavy episodic drinking by respondents was associated with a threefold increase in victimisation involving alcohol, and doubling of perpetration of aggression involving alcohol. Conclusion In a cross-section of households, “counts” of aggressive acts do not reflect the reality of gender differences. The frequency of heavy drinking episodes is associated with the occurrence of aggression involving alcohol within relationships, and the involvement of alcohol in an incident of aggression is associated with increased severity, fear and anger particularly for women.
- Grunwald, G. K., & Bell, M. L. (2011). Small sample estimation properties of longitudinal count models. Journal of Statistical Computation and Simulation, 81(9), 1067-1079. doi:10.1080/00949651003674144More infoMotivated by the need to validly analyse data from small longitudinal designs with count outcomes, we carried out a simulation study with a two-group longitudinal design with as few as five subjects per group and three measurements per subject. Various correlation structures related to autoregression and/or subject heterogeneity were used to simulate, most of which did not correspond to any of the methods being assessed and so induced some model misspecification. We evaluated validity (Type I error rate) and efficiency (power) for the interaction effect using several methods based on generalized linear mixed models (GLMM) or generalized estimating equations (GEE). Conclusions included that Type I error rates were too high for GEE using sandwich standard errors, and too low for GLMM. Generally, Type I error rate was improved with more subjects but not with more measurements per subjects, and both improved power. Many of our results differ from corresponding results in other cases (e.g. logistic models), em...
- Kidd, M. O., Bond, C. H., & Bell, M. L. (2011). Patients' perspectives of patient-centredness as important in musculoskeletal physiotherapy interactions: a qualitative study.. Physiotherapy, 97(2), 154-62. doi:10.1016/j.physio.2010.08.002More infoTo determine patients' perspectives of components of patient-centred physiotherapy and its essential elements..Qualitative study using semi-structured interviews to explore patients' judgements of patient-centred physiotherapy. Grounded theory was used to determine common themes among the interviews and develop theory iteratively from the data..Musculoskeletal outpatient physiotherapy at a provincial city hospital..Eight individuals who had recently received physiotherapy..Five categories of characteristics relating to patient-centred physiotherapy were generated from the data: the ability to communicate; confidence; knowledge and professionalism; an understanding of people and an ability to relate; and transparency of progress and outcome. These categories did not tend to occur in isolation, but formed a composite picture of patient-centred physiotherapy from the patient's perspective..This research elucidates and reinforces the importance of patient-centredness in physiotherapy, and suggests that patients may be the best judges of the affective, non-technical aspects of a given healthcare episode.
- Kypri, K., Cousins, K., Connor, J. L., & Bell, M. L. (2011). Alcohol involvement in aggression between intimate partners in New Zealand: a national cross-sectional study.. BMJ open, 1(1), e000065. doi:10.1136/bmjopen-2011-000065More infoTo examine the role of alcohol at the time of aggressive incidents between intimate partners in the general population by gender, by estimating (1) prevalence and severity of aggression, and drinking at the time, (2) associations of drinking at the time of the aggression with reported severity, anger and fear, and (3) association of usual drinking patterns with partner aggression..A national survey of 18-70-year-olds using an electoral roll sample obtained self-reported alcohol consumption, partner's alcohol consumption and details of the most severe partner aggression by the respondent and towards the respondent in the past 2 years. The mean scores for associated severity, anger and fear were analysed by gender and alcohol involvement. Multinomial models estimated associations of drinking patterns with aggression to and from the respondent..The response rate was 49% (n=1925). Men and women reported similar prevalence of victimisation and perpetration of aggression (11-15%). Alcohol was involved in more than 25% of incidents, and reported more by women than by men, particularly male-only drinking when the respondent was the victim. Women reported greater severity, anger and fear with victimisation than men, and drinking was associated with greater reported severity. Heavy episodic drinking by respondents was associated with a threefold increase in victimisation and doubling of perpetration of aggression involving alcohol. Heavy episodic drinking by either partner was also associated with drinking being involved in reported aggression..The experience of intimate-partner aggression in a cross-section of households differs by gender and the involvement of alcohol, and 'counts' of aggressive acts in a population-based survey do not reflect the reality of gender differences. Heavy episodic drinking patterns are associated with more aggression involving alcohol within relationships, and alcohol involvement is associated with increased severity.
- Ramrakha, S., Paul, C., Moffitt, T. E., Dickson, N., Caspi, A., & Bell, M. L. (2011). The relationship between multiple sex partners and anxiety, depression and substance dependence disorders: a cohort study. The Journal of Sexual Medicine, 8, 258-258.More infoChanges in sexual behavior have resulted in longer periods of multiple serial or concurrent relationships. This study investigated the effects of multiple heterosexual partners on mental health, specifically, whether higher numbers of partners were linked to later anxiety, depression, and substance dependency. Data from the Dunedin Multidisciplinary Health and Development Study, a prospective, longitudinal study of a birth cohort born in 1972–1973 in Dunedin, New Zealand were used. The relationship between numbers of sex partners over three age periods (18–20, 21–25, and 26–32 years) and diagnoses of anxiety, depression, and substance dependence disorder at 21, 26, and 32 years were examined, using logistic regression. Interaction by gender was examined. Adjustment was made for prior mental health status. There was no significant association between number of sex partners and later anxiety and depression. Increasing numbers of sex partners were associated with increasing risk of substance dependence disorder at all three ages. The association was stronger for women and remained after adjusting for prior disorder. For women reporting 2.5 or more partners per year, compared to 0–1 partners, the adjusted odd ratios (and 95 % CIs) were 9.6 (4.4–20.9), 7.3 (2.5–21.3), and 17.5 (3.5–88.1) at 21, 26, and 32 years, respectively. Analyses using new cases of these disorders showed similar patterns. This study established a strong association between number of sex partners and later substance disorder, especially for women, which persisted beyond prior substance use and mental health problems more generally. The reasons for this association deserve investigation.
- Sze, M., Mikhail, M., Iedema, R., Hui, R., Goldstein, D., Eisenbruch, M., Dong, S., Butow, P., Bell, M. L., Ashgari, R., Aldridge, L., & Abdo, S. (2011). Grappling with cultural differences; communication between oncologists and immigrant cancer patients with and without interpreters.. Patient education and counseling, 84(3), 398-405. doi:10.1016/j.pec.2011.01.035More infoImmigrants report challenges communicating with their health team. This study compared oncology consultations of immigrants with and without interpreters vs Anglo-Australian patients..Patients with newly diagnosed incurable cancer who had immigrated from Arabic, Chinese or Greek speaking countries or were Anglo-Australian, and family members, were recruited from 10 medical oncologists in 9 hospitals. Two consultations from each patient were audio-taped, transcribed, translated into English and coded..Seventy-eight patients (47 immigrant and 31 Anglo-Australian) and 115 family members (77 immigrant and 38 Anglo Australian) participated in 141 audio-taped consultations. Doctors spoke less to immigrants with interpreters than to Anglo-Australians (1443 vs. 2246 words, p=0.0001), spent proportionally less time on cancer related issues (p=0.005) and summarising and informing (p≤0.003) and more time on other medical issues (p=0.0008) and directly advising (p=0.0008). Immigrants with interpreters gave more high intensity cues (10.4 vs 7.4). Twenty percent of cues were not interpreted. Doctors tended to delay responses to or ignore more immigrant than Anglo-Australian cues (13% vs 5%, p=0.06)..Immigrant cancer patients with interpreters experience different interactions with their doctors than Anglo-Australians, which may compromise their well-being and decisions..Guidelines and proven training programmes are needed to improve communication with immigrant patients, particularly those with interpreters.
- Thewes, B., Sharpe, L., Patel, D., Clarke, S., & Bell, M. L. (2011). Using the Distress Thermometer and Hospital Anxiety and Depression Scale to screen for psychosocial morbidity in patients diagnosed with colorectal cancer.. Journal of affective disorders, 131(1-3), 412-6. doi:10.1016/j.jad.2010.11.014More infoThe Distress Thermometer (DT) and Hospital Anxiety and Depression Scale (HADS) are commonly used within oncology settings. However there is a paucity of research comparing these measures to gold standard structured clinical interviews assessing for clinical disorders. The aim of this study is to establish the sensitivity, specificity and optimal cut-off scores on these measures when compared to a clinical interview..Ninety-nine patients with colorectal cancer completed the DT and HADS and a psychologist-administered gold standard structured clinical interview (the Composite International Diagnostic Interview-CIDI). Receiver Operator Characteristic analyses (ROC) were conducted to establish the optimal cut-off score on the DT and HADS to identify clinical disorders based on the CIDI..Seventeen patients met criteria for a clinical disorder in the sample. A cut-off score of 4 on the DT indicated acceptable sensitivity (60%) and specificity (67%) to detect a current clinical disorder, while the optimal cut-off for the HADS was 10 (sensitivity=73%, specificity=72%). The area under the ROC values were 0.66 for the DT (95% CI: 0.51, 0.82) and 0.78 for the HADS (95% CI: 0.67, 0.90). The difference in AUC between the two measures was not statistically significant..The limitations to the design and methodology of the study are discussed..The single item DT performed fairly, however not as well as the longer HADS in identifying clinical disorders amongst oncology patients, particularly anxiety disorders.
- Roode, T. V., Paul, C., Jiang, Z. J., Dickson, N. P., & Bell, M. L. (2010). Consistency and reliability of self-reported lifetime number of heterosexual partners by gender and age in a cohort study.. Sexually transmitted diseases, 37(7), 425-31. doi:10.1097/olq.0b013e3181d13ed8More infoThe reported number of sexual partners is a variable used extensively in sexual health research. However, the reliability and consistency of this measure, and the statistical assessment of these attributes, are not well understood..Using data at ages 21, 26, and 32 years from a New Zealand birth cohort, we compared responses on the lifetime number of heterosexual sex partners to assess reliability and consistency. Differences by gender and age were considered, and the effect of number of sexual partners. A variety of analytical methods were used to explore statistical challenges of these data including variance estimation, fractional polynomial transformations, and quantile regression..We found some level of discrepancy between reports of the number of sexual partners when assessed at different times is common, driven by those reporting a high number of partners who were disproportionately men. Men reported a higher lifetime number of partners than women at each age, and there were statistically significant differences by gender in (a) consistency between reports at different ages, and (b) reliability of reports as measured by both the Intraclass Correlation Coefficient and the Kappa statistic..When considering reliability, multiple statistical approaches are necessary or conclusions can be misleading. Variance components should be examined when considering the Intraclass Correlation Coefficient. When modelling, robust methods like fractional polynomials and quantile regression should be employed to accommodate nonlinearity. Sensitivity analyses excluding participants whose partner number is in the upper 5% to 25% are informative, as these were shown to have the highest discrepancies.
- Bagge, P. J., Milosavljevic, S., Hendrick, P., Bell, M. L., & Bagge, P. J. (2009). Can accelerometry be used to discriminate levels of activity?. Ergonomics, 52(8), 1019-25. doi:10.1080/00140130902846464More infoThe aims of this study were to investigate the associations between an activity logbook and the RT3 accelerometer and to assess whether the RT3 can discriminate activity levels in healthy adults. Ten participants completed two trials wearing an RT3 accelerometer over a 4-6 h period and completed a detailed activity log. Results showed a poor correlation between the RT3 in moderate activities (r = 0.22) in comparison to low (r = 0.52) and hard (r = 0.70) from the logbook. A significant difference was found in average RT3 vector magnitude (VM) counts/min in each activity level (p < 0.0001). Discriminant analysis demonstrated that an RT3VM counts/min value of approximately 500 was found to have high sensitivity (88%), and specificity (88%) for discriminating between low and moderate activity levels from the logbook. This study found that accelerometry has the potential to discriminate activity levels in free living. This study is the first to investigate whether tri-axial accelerometry can discriminate different levels of free-living activity recorded in an activity logbook. The RT3 accelerometer can discriminate between low and moderate physical activities and offers a methodology that may be applicable to future research in occupational settings.
- Milosavljevic, S., Bussey, M. D., & Bell, M. L. (2009). Sex differences in the pattern of innominate motion during passive hip abduction and external rotation.. Manual therapy, 14(5), 514-9. doi:10.1016/j.math.2008.09.004More infoThe objective of the study was to evaluate sex differences in the pattern of innominate motion about the sacroiliac joint (SIJ) during hip movement. Although the magnitude of intrinsic SIJ motion is influenced by joint congruence and ligament elasticity sex differences in pelvic joint kinematics are under-investigated. Forty healthy and active males and females between the ages of 18 and 35 were recruited. 3D motion of the innominate bones and femur were recorded with a magnetic tracking device as the hips were loaded in standardised increments of 10 degrees in 3 positions - external rotation (ER), abduction (AB), and combined external rotation and abduction (AB+ER). While females had greater overall innominate motion, two distinct sex dominant patterns emerged. Patterns of innominate motion also differed when load was applied to the dominant rather than non-dominant limb. As the main motion within the pelvis is intrinsic, the results of the present study point to a differing viscoelastic response and different movement strategies to passive load between the sexes. In addition, careful attention to limb dominance should be considered when testing SIJ motion.
- Milosavljevic, S., Bussey, M. D., & Bell, M. L. (2009). The influence of hip abduction and external rotation on sacroiliac motion.. Manual therapy, 14(5), 520-5. doi:10.1016/j.math.2008.08.009More infoAlthough the sacroiliac joint (SIJ) is conventionally accepted as a sagittal joint with little mobility in other planes, recent research has shown evidence for reduced hip abduction and axial rotation in patients with sacroiliac pain. A sample of healthy individuals was investigated to determine whether innominate motion about the sacroiliac joint can be predicted from abduction and external rotation displacement of the femur. The motion of the innominate and femur were tracked as the hip was passively rotated by standardized increments of 10 degrees into (1) abduction; (2) external rotation; and (3) a combination of external rotation and abduction. Although sagittal and transverse plane innominate motion both increased significantly as the hip was rotated further into either abduction or external rotation, external rotation was the strongest predictor of change in innominate angle. A combination of external rotation and abduction led to greater increases in these innominate angles at a smaller degree of hip rotation. The results support the use of abduction and external rotation hip displacements (both singularly and in combination) for assessing SIJ mobility at least in the axes investigated. Further research that investigates the use of these tests in people with SIJ disorders is warranted.
- Milosavljevic, S., Melloh, M., Mcdonough, S. M., Hurley, D. A., Hendrick, P., Hale, L., Bell, M. L., & Baxter, D. G. (2009). Does physical activity change predict functional recovery in low back pain? Protocol for a prospective cohort study.. BMC musculoskeletal disorders, 10(1), 136. doi:10.1186/1471-2474-10-136More infoActivity advice and prescription are commonly used in the management of low back pain (LBP). Although there is evidence for advising patients with LBP to remain active, facilitating both recovery and return to work, to date no research has assessed whether objective measurements of free living physical activity (PA) can predict outcome, recovery and course of LBP..An observational longitudinal study will investigate PA levels in a cohort of community-dwelling working age adults with acute and sub-acute LBP. Each participant's PA level, functional status, mood, fear avoidance behaviours, and levels of pain, psychological distress and occupational activity will be measured on three occasions during for 1 week periods at baseline, 3 months, and 1 year. Physical activity levels will be measured by self report, RT3 triaxial accelerometer, and activity recall questionnaires. The primary outcome measure of functional recovery will be the Roland Morris Disability Questionnaire (RMDQ). Free living PA levels and changes in functional status will be quantified in order to look at predictive relationships between levels and changes in free living PA and functional recovery in a LBP population..This research will investigate levels and changes in activity levels of an acute LBP cohort and the predictive relationship to LBP recovery. The results will assess whether occupational, psychological and behavioural factors affect the relationship between free living PA and LBP recovery. Results from this research will help to determine the strength of evidence supporting international guidelines that recommend restoration of normal activity in managing LBP..[Clinical Trial Registration Number, ACTRN12609000282280].
- Reeder, A. I., Hammond, V. A., Gray, A. R., & Bell, M. L. (2008). Are workers or their workplaces the key to occupational sun protection?. Health promotion journal of Australia : official journal of Australian Association of Health Promotion Professionals, 19(2), 97-101. doi:10.1071/he08097More infoHigh levels of sun exposure and skin cancer are experienced by outdoor workers. To develop effective preventive strategies it is important to understand which factors predict sun protection use..Outdoor workers (n=74) in Central Otago, New Zealand, completed a questionnaire and recorded sun protection practices for five consecutive working days, January-March 2007..Sun protection was predicted by beliefs of personal susceptibility to skin cancer, suntan attitudes, and perceived workplace support, but not knowledge..Both individual and workplace factors influence outdoor workers' sun protection.
- Schultz, M., Karageorge, G., Howard, R., Harselaar, K. V., Derrett, S., Bell, M. L., & Basford, P. (2008). Post-procedure surveillance in liver biopsy: how long is long enough?. The New Zealand medical journal, 121(1280), 8-14.More infoTo assess the incidence of complications following liver biopsy and the impact of pre-procedural pethidine on complications and analgesia administration..A retrospective audit of percutaneous liver biopsies undertaken at Dunedin Public Hospital (2001-2006). Patients' medical files were consulted for demographics, biopsy indication, complications, frequency, and timing of analgesia..447 biopsies were analysed. Primary indications included: hepatitis C (38.8%), abnormal liver function tests (18.3%), methotrexate therapy (12.5%), and malignancy (10.3%). 303 (68%) biopsies resulted in no complications. Major complications were not experienced. Minor complications included: pain (32.2%), hypotension (1.3%), nausea/vomiting (0.9%), and alcohol withdrawal (0.2%). More females (47%) than males (31%) reported complications. Post-procedural analgesia was administered in 31% of biopsies; only 9% required analgesia more than 2 hours after biopsy. Patients who had pre-procedural pethidine experienced similar rates of complications as patients not receiving pre-procedural pethidine, but received less post-procedural opiate analgesia..No major complications occurred, whilst the rate of minor complications was comparable with previous studies. Pain was the most common complication, although use of analgesia after 2 hours of observation was low. Our findings suggest that post-procedural observation may safely be reduced to two hours but it is currently unknown if early mobilisation following discharge will lead to complications.
- Shroyer, A. L., Mcdonald, G. O., Grunwald, G. K., Grover, F. L., Bell, M. R., Bell, M. L., & Baltz, J. H. (2008). Does preoperative hemoglobin independently predict short-term outcomes after coronary artery bypass graft surgery?. The Annals of thoracic surgery, 86(5), 1415-23. doi:10.1016/j.athoracsur.2008.07.088More infoThe role of preoperative hemoglobin in predicting short-term coronary artery bypass graft (CABG) surgery outcomes has not been well established. This study investigated the association between preoperative hemoglobin level with 30-day operative mortality and perioperative complications..For the period from 1997 to 2005, the Department of Veterans Affairs Continuous Improvement in Cardiac Surgery Program database was used to extract 36,658 CABG-only deidentified records for patients undergoing cardiopulmonary bypass. Univariate and multivariate statistical models were used to predict both mortality and morbidity outcomes for varying levels of hemoglobin..Unadjusted odds of 30-day operative mortality for patients with preoperative hemoglobin level less than 10 g/dL were 2.37 times higher than for patients with hemoglobin levels of 10 g/dL or greater (95% confidence interval: 1.84 to 3.05; p < 0.0001). Multivariable effect upon 30-day operative mortality decreased considerably (odds ratio = 1.29, 95% confidence interval: 0.99 to 1.68; p = 0.064)..As several risk factors may occur concurrently with low hemoglobin, preoperative hemoglobin level less than 10 g/dL was not a strong independent predictor of 30-day operative mortality or perioperative morbidity in multivariate models for on-pump CABG-only patients. Hemoglobin and serum creatinine were correlated, with creatinine exhibiting the stronger association with mortality. These findings suggest that moderate or severe anemia may be intertwined with other risk factors, such as serum creatinine or congestive heart failure. For a CABG patient subgroup presenting with a complex clinical preoperative profile, therefore, risk-model approaches may be inherently limited in separately identifying the predictors of anemic patients' outcomes.
- Sims, S. T., Rehrer, N. J., Cotter, J. D., & Bell, M. L. (2008). Endogenous and Exogenous female sex hormones and renal handling: effects of sodium loading on plasma volume at rest. The FASEB Journal, 22(S2), 120-120. doi:10.1096/fasebj.22.2_supplement.120
- Sims, S. T., Rehrer, N. J., Cotter, J. D., & Bell, M. L. (2008). Endogenous and exogenous female sex hormones and renal electrolyte handling: effects of an acute sodium load on plasma volume at rest.. Journal of applied physiology, 105(1), 121-7. doi:10.1152/japplphysiol.01331.2007More infoThis study was conducted to investigate effects of an acute sodium load on resting plasma volume (PV) and renal mechanisms across the menstrual cycle of endurance-trained women with natural (NAT) or oral contraceptive pill (OCP) controlled cycles. Twelve women were assigned to one of two groups, according to their usage status: 1) OCP [n = 6, 29 yr (SD 6), 59.4 kg (SD 3.2)], or 2) NAT [n = 6, 24 yr (SD 5), 61.3 kg (SD 3.6)]. The sodium load was administered as a concentrated sodium chloride/citrate beverage (164 mmol Na(+)/l, 253 mosmol/kgH(2)O, 10 ml/kg body mass) during the last high-hormone week of the OCP cycle (OCP(high)) or late luteal phase of the NAT cycle (NAT(high)) and during the low-hormone sugar pill week of OCP (OCP(low)) or early follicular phase of the NAT cycle (NAT(low)). The beverage ( approximately 628 ml) was ingested in seven portions across 60 min. Over the next 4 h, PV expanded more in the low-hormone phase for both groups (time-averaged change): OCP(low) 6.1% (SD 1.1) and NAT(low) 5.4% (SD 1.2) vs. OCP(high) 3.9% (SD 0.9) and NAT(high) 3.5% (SD 0.8) (P = 0.02). The arginine vasopressin increased less in the low-hormone phase [1.63 (SD 0.2) and 1.30 pg/ml (SD 0.2) vs. 1.82 (SD 0.3) and 1.57 pg/ml (SD 0.5), P = 0.0001], as did plasma aldosterone concentration ( approximately 64% lower, P = 0.0001). Thus PV increased more and renal hormone sensitivity was decreased in the low-hormone menstrual phase following sodium/fluid ingestion, irrespective of OCP usage.
- Earl, J. B., Britt, S. G., & Bell, M. L. (2007). Two types of Drosophila R7 photoreceptor cells are arranged randomly: a model for stochastic cell-fate determination.. The Journal of comparative neurology, 502(1), 75-85. doi:10.1002/cne.21298More infoThe R7 photoreceptor cells of the Drosophila retina are ultraviolet sensitive and are thought to mediate color discrimination and polarized light detection. In addition, there is growing evidence that the color sensitivity of the R8 cell within an individual ommatidium is regulated by a genetic switch that depends on the type of R7 cell adjacent to it. Here we examine the organization of the two major types of R7 cells by three different rigorous statistical methods and present evidence that they are arranged randomly and independently. First, we performed L-function analyses to test whether the organization of R7 cells (and the relationship between them) is regular, clustered, or completely spatially random. Next, we used generalized linear mixed models to test whether the proportion of R7 cell neighbors differs from their prevalence within the eye as a whole. Finally, we conducted a series of simulations to test whether the proportion of R7 cell neighbors differs from that in a random simulation. In each case, we found evidence that the organization of the two types of R7 cells is random and independent, suggesting that R7 cells in neighboring ommatidia are unlikely to interact and influence each other's identity and may be determined stochastically in a cell-autonomous manner. Compared with traditional lineage or inductive mechanisms, this may represent a novel mechanism of cell fate determination based on noisy or stochastic gene expression in which the differentiation of an individual R7 cell is a random event but the proportions of R7 cell subtypes are regulated.
- Milosavljevic, S., Milburn, P. D., Hickey, B. W., & Bell, M. L. (2007). Accuracy and reliability of observational motion analysis in identifying shoulder symptoms.. Manual therapy, 12(3), 263-70. doi:10.1016/j.math.2006.05.005More infoAberrations in shoulder movement patterns are believed to be associated with the presence of shoulder symptoms. However, the detection of movement aberrations has not been rigorously investigated. It is possible that manipulative physiotherapists use the clinical history to prejudge the existence of aberrations, rather than the actual observation of the movement pattern itself. There is a need to determine whether physiotherapists, in the absence of a clinical history, can relate observed anomalies of shoulder movement to the presence of symptoms and to determine the reliability for observation of such anomalous shoulder movement..The sample comprised of 9 symptomatic subjects recruited from four physiotherapy clinics in Christchurch, New Zealand and a further 11 asymptomatic subjects recruited from Christchurch's general population. They were videotaped performing shoulder flexion, abduction, and scapular plane abduction. The video-recordings were evaluated by 11 manipulative physiotherapists who did not know which subjects were symptomatic and who were thus required to judge the symptomatic status as: asymptomatic, symptomatic left, symptomatic right or symptomatic both. Additionally, each physiotherapist completed a survey on each of the 20 subjects regarding the type of movement anomaly that was perceived (e.g. too much scapular elevation, too little glenohumeral movement, etc). Classification accuracy (percentage of correct responses) and agreement (kappa) among physiotherapists were computed..Out of the 220 responses by the physiotherapists regarding symptomatic status, 58% were correct, with 68% asymptomatic, 71% symptomatic left and 30% symptomatic right subjects correctly classified. Reliability analysis showed kappa statistics for all subjects was 0.23, for asymptomatic subjects 0.22, symptomatic left 0.34, and symptomatic right 0.17. Only five subjects had two or more evaluators agree on the type of anomalous movement..Although movement analysis is considered an integral part of a physiotherapist's skill this research has shown that a sample of experienced manipulative physiotherapists had difficulty in determining the symptomatic status of patients with clinically diagnosed shoulder complaints by movement analysis alone.
- Ramrakha, S., Paul, C., Moffitt, T. E., Dickson, N., Caspi, A., & Bell, M. L. (2007). Childhood behavior problems linked to sexual risk taking in young adulthood: a birth cohort study.. Journal of the American Academy of Child and Adolescent Psychiatry, 46(10), 1272-1279. doi:10.1097/chi.0b013e3180f6340eMore infoTo study whether behavioral and emotional problems during childhood predicted early sexual debut, risky sex at age 21 years, and sexually transmitted infections up to age 21 years. Some possible mediational pathways were also explored..Participants were enrolled in the Dunedin Multidisciplinary Health and Development Study (n = 1,037), a prospective, longitudinal study of a New Zealand birth cohort born in 1972-1973. Data obtained at ages 5, 7, 9, 11, 13, 15, and 21 years were used. Adjustment was made for gender, socioeconomic status, parenting factors, and residence changes..High levels of antisocial behavior between age 5 and 11 years were associated with increased odds of early sexual debut (adjusted odds ratio [AOR] 2.17, 95% confidence [CI] 1.34-3.54) and risky sex (AOR 1.88, 95% CI 1.04-3.40). No relationship was observed between hyperactivity and later sexual health outcomes. In contrast, high levels of anxiety were associated with reduced odds of risky sex (AOR 0.45, 95% CI 0.25-0.80) and sexually transmitted infections (AOR 0.34, 95% CI 0.17-0.70). Involvement with delinquent peers explained some of the association between antisocial behavior and early sexual debut and risky sex. A poor relationship with parents also explained some of the association between antisocial behavior and early sexual debut..The findings demonstrate links between behavioral and emotional problems occurring early in life and later deleterious sexual health outcomes. Targeting antisocial behavior and teaching accurate appraisals of danger during childhood may help mitigate these negative consequences.
- Sims, S. T., Rehrer, N. J., Cotter, J. D., & Bell, M. L. (2007). Preexercise sodium loading aids fluid balance and endurance for women exercising in the heat.. Journal of applied physiology, 103(2), 534-41. doi:10.1152/japplphysiol.01203.2006More infoThis study was conducted during the high-hormone phase of both natural and oral contraceptive pill (OCP)-mediated menstrual cycles to determine whether preexercise ingestion of a concentrated sodium beverage would increase plasma volume (PV), reduce physiological strain, and aid endurance of moderately trained women cycling in warm conditions. Thirteen trained cyclists [peak O(2) uptake 52 ml x kg(-1) x min(-1) (SD 2), age 26 yr (SD 6), weight 60.8 kg (SD 5)] who were oral contraceptive users (n = 6) or not (n = 7) completed this double-blind, crossover experiment. Cyclists ingested a concentrated-sodium (High Na(+): 164 mmol Na(+)/l) or low-sodium (Low Na(+): 10 mmol Na(+)/l) beverage (10 ml/kg) before cycling to exhaustion at 70% Peak O(2) uptake in warm conditions (32 degrees C, 50% relative humidity, air velocity 4.5 m/s). Beverage (approximately 628 ml) was ingested in seven portions across 60 min beginning 105 min before exercise, with no additional fluid given until the end of the trial. Trials were separated by one to two menstrual cycles. High Na(+) increased PV (calculated from hematocrit and hemoglobin concentration) before exercise, whereas Low Na(+) did not [-4.4 (SD 1.1) vs. -1.9% (SD 1.3); 95% confidence interval: for the difference 5.20, 6.92; P < 0.0001], and it involved greater time to exhaustion [98.8 (SD 25.6) vs. 78.7 (SD 24.6) min; 95% confidence interval: 13.3, 26.8; P < 0.0001]. Core temperature rose more quickly with Low Na(+) [1.6 degrees C/h (SD 0.2)] than High Na(+) [1.2 degrees C/h (SD 0.2); P = 0.04]. Plasma [AVP], [Na(+)] concentration, and osmolality, and urine volume, [Na(+)], and osmolality decreased with sodium loading (P < 0.05) independent of pill usage. Thus preexercise ingestion of a concentrated sodium beverage increased PV, reduced thermoregulatory strain, and increased exercise capacity for women in the high-hormone phase of natural and oral contraceptive pill-mediated menstrual cycles, in warm conditions.
- Sims, S. T., Rehrer, N. J., Cotter, J. D., & Bell, M. L. (2007). Sodium Loading Aids Fluid Balance And Exercise Tolerance For Women With Natural And Controlled Menstrual Cycles.: 729. Medicine and Science in Sports and Exercise, 39(Supplement), S50. doi:10.1249/01.mss.0000273088.71953.80
- Gueimonde, M., Sakata, S., Isolauri, E., Benno, Y., Salminen, S., Westcott, J. E., Robinson, C., Krebs, N. F., Kalliom??ki, M., Hambidge, K. M., Butler, N., & Bell, M. L. (2006). Meat as a first complementary food for breastfed infants: feasibility and impact on zinc intake and status.. Journal of Pediatric Gastroenterology and Nutrition, 42(2), 207-214. doi:10.1097/01.mpg.0000189346.25172.fdMore infoABSTRACTBackground:Establishment of the gut microbiota at birth provides a substantial source of microbial stimuli for the maturation of the immune system. Deviations in this process precede the development of specific diseases providing the rationale for the use of probiotics to counteract them.Obj
- Skegg, D. C., Paul, C., Parkin, L., Herbison, P., Herbison, G. P., & Bell, M. L. (2006). Air travel and fatal pulmonary embolism.. Thrombosis and Haemostasis, 95(5), 807-814. doi:10.1160/th05-12-0813More infoAlthough long-distance air travel is commonly regarded as a risk factor for venous thromboembolism, the risk of clinically important events has not been well defined.We estimated the absolute risk of dying from pulmonary embolism following longdistance air travel in a national population-based descriptive study of 121 men and women who were aged 15–59 years (the age range in which the majority of international arrivals are found) and whose underlying cause of death was certified as codes 415.1, 451, or 453 of the International Classification of Diseases (ninth revision). Eleven cases had undertaken longdistance air travel in the four weeks before the onset of the fatal episode. The estimated risks of fatal pulmonary embolism following a flight of at least three hours’ duration were 0.5 (95% CI 0.2–1.2) and 0.6 (95% CI 0.2–1.4) per million arrivals for overseas visitors and New Zealand residents, respectively. For air travel of more than eight hours’ duration, the risk in New Zealand residents was 1.3 (95% CI 0.4–3.0) per million arrivals.We also conducted a case-control study based on those cases who were normally resident in New Zealand and registered on the electoral roll (n=99 ). For each case, four controls matched for sex, age, and electorate, were randomly selected from the electoral roll. In the key analysis (based on 88 cases and 334 controls), the adjusted odds ratio for travellers who had flown for more than eight hours was 7.9 (95% CI 1.1–55.1) compared with those who did not undertake a long-distance flight. Longdistance air travellers have a higher risk of dying from pulmonary embolism than non-travellers, but the absolute risk in people aged 15–59 years appears to be very small.
- Warren, J., Sullivan, S. J., Schneiders, A. G., & Bell, M. L. (2006). Repeated single-limb postural stability testing elicits a practice effect.. Physical therapy in sport : official journal of the Association of Chartered Physiotherapists in Sports Medicine, 7(4), 185-90. doi:10.1016/j.ptsp.2006.06.002More infoTo document the effects of repeated testing on the single-leg stance balance task..Single cohort repeated measures..Laboratory in an educational institution..Thirty-two healthy males and females..The number of errors (deviations from the required posture) during each 20-s trial summed over the eight conditions recorded on six occasions..There was a statistically significant (p=.0013) decrease in the number of errors recorded over the six sessions, from 26.8 (95% CI: 23.1-30.5) to 19.7 (95% CI: 16.3-23.1). Linear regression confirmed a systematic decrease of 1.5 errors per session on average (95% CI: 1.0-1.9; p
- Weil, K. M., Shepard, T. Y., Sharp, T. A., Hill, J. O., Hernandez, T. L., Grunwald, G. K., Francis, C. C., Eckel, R. H., & Bell, M. L. (2006). Carbohydrate balance predicts weight and fat gain in adults.. The American journal of clinical nutrition, 83(4), 803-8. doi:10.1093/ajcn/83.4.803More infoThe prevention and treatment of obesity is a public health challenge..We investigated the effects of dietary composition, insulin sensitivity (S(I)), and energy balance on predicted changes in body composition..In a randomized crossover design study, 39 normal-weight (n = 23), overweight (n = 8), and obese (n = 8) men and women (aged 25-36 y) each followed a 15-d isocaloric high-fat (HF; 50% fat) and high-carbohydrate [HC; 55% carbohydrate (CHO)] diet with a 4-6-wk washout period during the first year. During each treatment, energy balance was measured while the subjects were inactive by using indirect calorimetry on day 15, and S(I) was measured by using a euglycemic clamp study (40 mU . m(-2) . min(-1)) on day 16. Weight and body composition were then measured annually for 4 y. The outcomes for fat mass, percentage body fat, and weight were measured by using a linear 2-stage mixed model..CHO balance (day 15) and S(I) (day 16) on the HC diet were highly and significantly correlated (r = 0.55, P < 0.001). On the HC diet, the subjects who had a higher positive CHO balance (day 15) gained less fat mass (P < 0.001), percentage body fat (P = 0.006), and weight (P = 0.024) over time. When adjusted for S(I), CHO balance remained a significant predictor of changes in fat mass (P = 0.021) and percentage body fat (P = 0.025)..On a HC diet, the subjects who had a higher positive CHO balance on day 15 while they were inactive gained less fat mass during 4 y, a predictive effect independent of S(I). As suggested in rodents, the capacity to expand the glycogen pool might reduce energy intake and protect against fat and weight gain.
- Walker, R. J., Gerrard, D. F., Cotter, J. D., Bell, M. L., & Baker, J. (2005). Effects of indomethacin and celecoxib on renal function in athletes.. Medicine and science in sports and exercise, 37(5), 712-7. doi:10.1249/01.mss.0000162700.66214.ceMore infoStrenuous exercise induces a marked reduction in renal hemodynamics. Prostaglandins (PG) play an important role in maintaining renal integrity in the face of hemodynamic changes. Inhibition of cyclooxygenase (COX) and thus PG formation can further compromise renal perfusion. The role of selective COX-2 inhibition on renal hemodynamics during exercise has not been investigated..Twelve healthy males (22-47 yr) took part in a randomized placebo controlled study investigating the effects of nonselective COX inhibition (indomethacin) and COX-2 selective inhibition (celecoxib) on renal hemodynamics during exercise. Renal blood flow (RBF), glomerular filtration rate (GFR), and free water clearance were measured using standard clearance techniques. Each experimental session was performed at least a week apart. The medications were taken for 36 h before study with the last dose at 0700 h on the day of study. Following baseline studies, each participant exercised for 30 min at 80% of their maximal aerobic power. Renal function was monitored for 2 h post-recovery..RBF and GFR fell by 40% after exercise with no significant difference between placebo, indomethacin, or celecoxib. Indomethacin (-2.43 +/- 0.95 mL x min(-1), P < 0.007) and celecoxib (-3.88 +/- 0.94 mL x min(-1), P < 0.0001) significantly reduced free water clearance compared with placebo during recovery..This study has confirmed that selective and nonselective COX inhibition can induce significant inhibition of free water clearance, indicating that these acute changes are regulated predominantly via COX-2. Acute cerebral edema with hyponatremia has been reported after major endurance sporting events. Identifiable risk factors include excessive hydration and use of NSAID. Impaired free water clearance during exercise potentiated by COX inhibition provides a pathophysiological explanation for these observations.
- Grunwald, G. K., & Bell, M. L. (2004). Mixed models for the analysis of replicated spatial point patterns.. Biostatistics, 5(4), 633-48. doi:10.1093/biostatistics/kxh014More infoThe statistical methodology for the analysis of replicated spatial point patterns in complex designs such as those including replications is fairly undeveloped. A mixed model is developed in conjunction with maximum pseudolikelihood and generalized linear mixed modeling by extending Baddeley and Turner's (2000, Australian and New Zealand Journal of Statistics 42, 283-322) work on pseudolikelihood for single patterns. A simulation experiment is performed on parameter estimation. Fixed- and mixed-effect models are compared, and in some respects the mixed model is found to be superior. An example using the Strauss process for modeling neuron locations in post-mortem brain slices is shown.
- Higgins, J. A., Higbee, D. R., Donahoo, W. T., Brown, I. L., Bessesen, D. H., & Bell, M. L. (2004). Resistant starch consumption promotes lipid oxidation.. Nutrition & metabolism, 1(1), 8. doi:10.1186/1743-7075-1-8More infoBACKGROUND: Although the effects of resistant starch (RS) on postprandial glycemia and insulinemia have been extensively studied, little is known about the impact of RS on fat metabolism. This study examines the relationship between the RS content of a meal and postprandial/post-absorbative fat oxidation. RESULTS: 12 subjects consumed meals containing 0%, 2.7%, 5.4%, and 10.7% RS (as a percentage of total carbohydrate). Blood samples were taken and analyzed for glucose, insulin, triacylglycerol (TAG) and free fatty acid (FFA) concentrations. Respiratory quotient was measured hourly. The 0%, 5.4%, and 10.7% meals contained 50 muCi [1-14C]-triolein with breath samples collected hourly following the meal, and gluteal fat biopsies obtained at 0 and 24 h. RS, regardless of dose, had no effect on fasting or postprandial insulin, glucose, FFA or TAG concentration, nor on meal fat storage. However, data from indirect calorimetry and oxidation of [1-14C]-triolein to 14CO2 showed that addition of 5.4% RS to the diet significantly increased fat oxidation. In fact, postprandial oxidation of [1-14C]-triolein was 23% greater with the 5.4% RS meal than the 0% meal (p = 0.0062). CONCLUSIONS: These data indicate that replacement of 5.4% of total dietary carbohydrate with RS significantly increased post-prandial lipid oxidation and therefore could decrease fat accumulation in the long-term.
- Parker, M. A., Bell, M. L., & Barlow, L. A. (2004). Cell contact-dependent mechanisms specify taste bud pattern during a critical period early in embryonic development.. Developmental dynamics : an official publication of the American Association of Anatomists, 230(4), 630-42. doi:10.1002/dvdy.20086More infoAfter gastrulation, the pharyngeal endoderm is specified to give rise to taste receptor organs without further signaling from other embryonic tissues. We hypothesized that intercellular signaling might be responsible for the specification of taste buds. To test if and when this signaling was occurring, intercellular contacts were transiently disrupted in cultures of pharyngeal endoderm from axolotl embryos, and the number, size, and distribution of taste buds analyzed. Disruption of cell contacts at progressive time points, from neurula to late tail bud stages, revealed a critical period, during mid-tail bud stages, when disruption of cell contacts resulted in a significant increase in taste bud number and size. The spatial distribution of taste buds was also altered; taste buds were more clustered in explants disrupted during the critical period. These effects were not due to general alterations in mitosis and apoptosis. Rather, at least three aspects of taste bud patterning, i.e., number, size, and distribution, are governed by mechanisms dependent on normal cell contacts during a concise time window. Furthermore, our findings are consistent with specification of taste buds by means of lateral inhibitory signaling, which we hypothesize results from cell contact-dependent or short-range diffusible signals.
- Peters, J. C., Nysse, L. J., Melanson, E. L., Levine, J. A., Lanningham-foster, L., Knoll, J. R., Hill, J. O., Donahoo, W. T., & Bell, M. L. (2004). Commercially available pedometers: considerations for accurate step counting.. Preventive medicine, 39(2), 361-8. doi:10.1016/j.ypmed.2004.01.032More infoMany commercially available pedometers undercount, especially at slower speeds. We examined the effects of age, obesity, and self-selected walking speed on pedometer accuracy. We also compared the accuracy of piezoelectric and spring-levered pedometers at slow walking speeds..Study 1: 259 subjects walked on a motorized treadmill at two self-selected walking speeds. Steps were counted using a spring-levered pedometer. Study 2: 32 subjects walked on a motorized treadmill at slow walking (1.0-2.6 MPH) speeds. Steps were counted using spring-levered and piezoelectric pedometers..Study 1: self-selected walking speed and pedometer accuracy decreased with increasing age, weight, and body mass index (BMI). Accuracy was 71% below 2.0 MPH, 74-91% between 2.0 and 3.0 MPH, and 96% above 3.0 MPH. Decreased accuracy was best predicted by increasing age. Study 2: between 1.8 and 2.0 MPH, the accuracy of the piezoelectric pedometer (>97%) exceeded that of the spring-levered pedometers (52-95%). Even at 1.0 MPH, accuracy of the piezoelectric pedometer (56.4 +/- 33.8%) was superior to the spring-levered pedometers (7-20%)..Accuracy of all pedometers tested exceeded 96% at speeds 3.0 MPH, but decreased at slower walking speeds. In individuals that naturally ambulate at slower walking speeds (e.g., elderly), we recommend the use of more sensitive (e.g., piezoelectric) pedometers.
- Hall, J. M., Finger, T. E., & Bell, M. L. (2003). Disruption of sonic hedgehog signaling alters growth and patterning of lingual taste papillae.. Developmental biology, 255(2), 263-77. doi:10.1016/s0012-1606(02)00048-9More infoTaste buds on the anterior part of the tongue develop in conjunction with epithelial-mesenchymal specializations in the form of gustatory (taste) papillae. Sonic hedgehog (Shh) and Bone Morphogenetic Protein 4 (BMP4) are expressed in developing taste papillae, but the roles of these signaling molecules in specification of taste bud progenitors and in papillary morphogenesis are unclear. We show here that BMP4 is not expressed in the early tongue, but is precisely coexpressed with Shh in papillary placodes, which serve as a signaling center for both gustatory and papillary development. To elucidate the role of Shh, we used an in vitro model of mouse fungiform papillary development to determine the effects of two functional inhibitors of Shh signaling: anti-Shh (5E1) antibody and cyclopamine. Cultured E11.5 tongue explants express Shh and BMP4(LacZ) in a pattern similar to that of intact embryos, localizing to developing papillary placodes after 2 days in culture. Tongues cultured with 5E1 antibody continue to express these genes in papillary patterns but develop more papillae that are larger and closer together than in controls. Tongues cultured with cyclopamine have a dose-dependent expansion of Shh and BMP4(LacZ) expression domains. Both antibody-treated and cyclopamine-treated tongue explants also are smaller than controls. Taken together, these results suggest that, although Shh is not involved in the initial specification of papillary placodes, Shh does play two key roles during pmcry development: (1) as a morphogen that directs cells toward a nonpapillary fate, and (2) as a mitogen, causing expansion of the interplacodal epithelium and underlying mesenchyme.
- Peters, J. C., Melanson, E. L., Knoll, J. R., Hill, J. O., Donahoo, W. T., Coelho, L. B., & Bell, M. L. (2003). PREDICTING THE NET ENERGY COST OF WALKING AT SELF-SELECTED SPEEDS IN HEALTHY ADULTS. Medicine and Science in Sports and Exercise, 35(Supplement 1), S155. doi:10.1097/00005768-200305001-00855
- Weil, K. M., Stauffer, B. L., Poirier, P., Hernandez, T. L., Eckel, R. H., Desouza, C. A., Capell, W. H., & Bell, M. L. (2003). Short-term triglyceride lowering with fenofibrate improves vasodilator function in subjects with hypertriglyceridemia.. Arteriosclerosis, thrombosis, and vascular biology, 23(2), 307-13. doi:10.1161/01.atv.0000046230.02211.b4More infoThe objective of this study was to investigate the effects of lowering plasma triglycerides (TGs) on endothelial function and gain insight into the role played by free fatty acids (FFAs) in hypertriglyceridemia-associated vascular dysfunction..Eleven hypertriglyceridemic subjects without coronary artery disease, diabetes, elevated low-density lipoprotein cholesterol, tobacco use, or hypertension were studied using a randomized, double-blinded, crossover design (fenofibrate and placebo, 14 days). After each regimen, forearm blood flow was assessed by plethysmography in response to arterial acetylcholine, nitroprusside, and verapamil infusion. Hourly plasma TGs, FFA, glucose, and insulin were measured during a 24-hour feeding cycle to characterize the metabolic environment. Changes in plasma FFA after intravenous heparin were used to estimate typical FFA accumulation in the luminal endothelial microenvironment. Fenofibrate lowered plasma TG (P
- Westcott, J. E., Sian, L., Miller, L. V., Krebs, N. F., Hambidge, K. M., Grunwald, G. K., & Bell, M. L. (2003). Exchangeable zinc pool size in infants is related to key variables of zinc homeostasis.. The Journal of nutrition, 133(5 Suppl 1), 1498S-501S. doi:10.1093/jn/133.5.1498sMore infoThe exchangeable zinc pool (EZP) is the sum of the combined pools that exchange with zinc in the plasma within 48-72 h and is thought to be critical for zinc-dependent biological processes. The size of the EZP in adults has been found to be positively related to dietary zinc intake, daily absorbed zinc and fecal excretion of endogenous zinc. In this study, we examine data on EZP size in relation to variables of zinc homeostasis in normal infants on different feeding regimens. Data from 45 male infants who participated in one of four different studies contribute to the analysis. The feeding regimens include exclusive breastfeeding (n = 9; age, 2-5 mo); breastfeeding plus modest supplementation with cow's milk-based formula (n = 16; age, 3-4 mo); exclusive formula feeding (n = 4; age, 3-4 mo) and exclusive breastfeeding plus complementary foods (n =16; age, 7 mo). Fractional absorption was determined by fecal monitoring after oral administration of zinc-stable isotopes. Urine enrichment 4-8 d posttracer was used to determine endogenous fecal zinc (7-mo-old infants excepted) and EZP size. Univariate correlations and multivariate regression analyses were performed between EZP and age, weight, dietary zinc intake, fractional absorption, total absorbed zinc and endogenous fecal zinc. Results include no significant relationship between EZP size and age, body weight or fractional absorption but a positive relationship with daily absorbed zinc and endogenous fecal zinc excretion. We conclude that the amount of absorbed zinc is not tightly regulated, and that endogenous fecal zinc is dependent on and responsive to the zinc status of the organism.
- Tolan, K., Sidney, S., Sharp, T. A., Schmitz, K. H., Lewis, C. E., Hill, J. O., Grunwald, G. K., & Bell, M. L. (2002). Differences in resting metabolic rate between white and African-American young adults.. Obesity research, 10(8), 726-32. doi:10.1038/oby.2002.99More infoA reported lower resting metabolic rate (RMR) in African-American women than in white women could explain the higher prevalence of obesity in the former group. Little information is available on RMR in African-American men..We assessed RMR by indirect calorimetry and body composition by DXA in 395 adults ages 28 to 40 years (100 African-American men, 95 white men, 94 African-American women, and 106 white women), recruited from participants in the Coronary Artery Risk Development in Young Adults (CARDIA), Birmingham, Alabama, and Oakland, California, field centers..Using linear models, fat-free mass, fat mass, visceral fat, and age were significantly related to RMR, but the usual level of physical activity was not. After adjustment for these variables, mean RMR was significantly higher in whites (1665.07 +/- 10.78 kcal/d) than in African Americans (1585.05 +/- 11.02 kcal/d) by 80 +/- 16 kcal/d (p < 0.0001). The ethnic x gender interaction was not significant (p = 0.9512), indicating that the difference in RMR between African-American and white subjects was similar for men and women..RMR is approximately 5% higher in white than in African-American participants in CARDIA. The difference was the same for men and women and for lean and obese individuals. The prevalence of obesity is not higher in African-American men than in white men. Because of these reasons, we believe that RMR differences are unlikely to be a primary explanation for why African-American women are more prone to obesity than white women.
- Westcott, J. L., Westcott, J., Steirn, M., Miller, L. V., Krebs, N. F., Jalla, S., & Bell, M. L. (2002). Zinc absorption and exchangeable zinc pool sizes in breast-fed infants fed meat or cereal as first complementary food.. Journal of pediatric gastroenterology and nutrition, 34(1), 35-41. doi:10.1097/00005176-200201000-00009More infoThe aims of this study were to compare the absorption efficiency of zinc from rice cereal and meat, with and without human milk, in 7-month-old breast-fed infants and to compare the size of exchangeable zinc pools in the infants according to the assigned complementary food..Fractional absorption of zinc was measured in male infants using extrinsic labeling with a stable isotope of zinc in a test meal of either pureed beef (n = 9) or iron-fortified infant rice cereal (n = 9). The effect on fractional absorption of the addition of human milk to each complementary food was measured in each infant with a second oral zinc isotope. Fractional absorption was measured using fecal monitoring of isotope excretion, and exchangeable zinc pool size was calculated from isotopic enrichment in urine..Fractional absorption of zinc did not statistically differ between the beef (0.41 +/- 0.11) and cereal (0.36 +/- 0.05) test meals, although the trend showed that beef had higher fractional absorption than cereal. The higher intake of zinc from the beef versus cereal test meal resulted in a 16-fold greater amount of absorbed zinc ( P = 0.0002). The addition of human milk caused significant decreases in fractional absorption of zinc (0.07 +/- 0.02, P = 0.01) and absorbed zinc (0.04 +/- 0.01 mg, P < 0.0001). The size of the exchangeable zinc pool did not differ according to group but was strongly correlated with mean daily zinc intake ( r = 0.72, P = 0.003)..These results confirm that meat as a complementary food for breast-fed infants can provide a rich source of dietary zinc that is well absorbed. The significant positive correlation between zinc intake and exchangeable zinc pool size suggests that increasing zinc intake positively affects metabolically available zinc.
- Weil, K. M., Shepard, T. Y., Sharp, T. A., Hill, J. O., Grunwald, G. K., Eckel, R. H., & Bell, M. L. (2001). Occasional physical inactivity combined with a high-fat diet may be important in the development and maintenance of obesity in human subjects.. The American journal of clinical nutrition, 73(4), 703-8. doi:10.1093/ajcn/73.4.703More infoA better understanding of the environmental factors that contribute to obesity is imperative if any therapeutic effect on the increasing prevalence of overweight and obesity in the United States is to be achieved..This study examined the effect of the interaction of diet composition and physical inactivity on energy and fat balances..Thirty-five normal-weight and obese subjects were randomly assigned to either a 15-d isoenergetic high-carbohydrate (HC) or high-fat (HF) diet according to a crossover design. During the first 14 d, body weight and physical activity were maintained. On day 15, subjects spent 23 h in a whole-room indirect calorimeter and were fed a diet similar to that consumed during the previous 7 d while remaining physically inactive..Energy intakes required to maintain body weight stability during the first 14 d were similar between diets. Normal-weight and obese subjects consuming both diets had a positive energy balance on the sedentary day (day 15), suggesting that subjects were less active in the calorimeter. There was no significant effect of diet composition on total energy balance and total protein-energy balance on day 15; however, carbohydrate balance was more positive with the HC (2497.8 +/- 301.2 kJ) than with the HF (1159 +/- 301.2 kJ) diet (P = 0.0032). Most importantly, fat balance was more positive with the HF (1790.8 +/- 510.4 kJ) than with the HC (-62.8 +/- 510.4 kJ) diet (P = 0.0011)..Chronic consumption of a high-carbohydrate diet could provide some protection against body fat accumulation in persons with a pattern of physical activity that includes frequent sedentary days.
- Grunwald, G. K., Bell, M. L., Astrup, A., & Agerholm-larsen, L. (2000). The effect of a probiotic milk product on plasma cholesterol: a meta-analysis of short-term intervention studies.. European journal of clinical nutrition, 54(11), 856-60. doi:10.1038/sj.ejcn.1601104More infoCertain fermented dairy milk products may have beneficial effects on plasma cholesterol levels. However, a number of studies have produced conflicting results as to whether dietary supplementation by a probiotic dairy product containing the bacteria culture Causido(R) reduces plasma cholesterol..To conduct a meta-analysis of intervention studies to evaluate the effect of the Causido(R) culture on plasma total cholesterol and low-density lipoprotein (LDL)-cholesterol. THE PROBIOTIC MILK PRODUCT: The yoghurt product Gaio(R) is fermented with Causido(R), composed of one strain of Enterococcus faecium (human species) with the proposed cholesterol-lowering effect, and two strains of Streptococcus thermophilus. STUDY INCLUSION AND DATA EXTRACTION: Six studies were identified from a literature search and from the yoghurt producer. All studies met the inclusion criteria. Summary data for plasma concentrations of total cholesterol and LDL-cholesterol were extracted from the original publications or by personal request to the authors. Data from 4-8 weeks of treatment duration was used..We performed a traditional meta-analysis where mean differences between intervention and control of the pre-post changes in total cholesterol and LDL-cholesterol were calculated, as well as 95% confidence intervals (CIs)..In the six studies included in the meta-analysis, the Gaio(R) interventions produced changes in total cholesterol above those of the control groups ranging from -0.02 to -1.02 mmol/l and in LDL-cholesterol ranging from -0.02 to -1.15 mmol/l. After inclusion of an open-label study, the meta-analysis of the double-blind studies showed that Gaio(R) as compared to the control group changed total cholesterol by -0.22 mmol/l (95% CI: -0.35 to -0.08, P
Proceedings Publications
- Bell, M., & Rabe, B. (2017). How are researchers handling missing data in noninferiority trials? A systematic review. In TRIALS, 18.
- Garcia, D. O., Valdez, L., Aceves, B., Campas, D., Loya, J., Hingle, M. D., Bell, M. L., Hooker, S. P., & McEwen, M. M. (2017). A GENDER-AND CULTURALLY-SENSITIVE WEIGHT LOSS INTERVENTION FOR HISPANIC MALES. In ANNALS OF BEHAVIORAL MEDICINE, 51.
- Johnson, S. B., Butow, P., Bell, M. L., Detering, K., Clayton, J., Silvester, W., Kiely, B. E., Clarke, S., Vaccaro, L., Stockler, M. R., & others, . (2017). A randomised Controlled Trial of an Advance Care Planning Intervention for Patients with Incurable Cancer. In ASIA-PACIFIC JOURNAL OF CLINICAL ONCOLOGY, 13.
Presentations
- Allen, A. M., Yuan, N. P., Wetheim, B., Krupski, L. A., Nair, U. S., & Bell, M. L. (2018, Spring). Gender Differences in Smoking Cessation outcomes Among Callers at a State Quitline. College on Problems of Drug Dependence. San Diego, CA.
- Van Horne, Y. O., Bell, M. L., Lothrop, N. Z., Wilkinson, S., Klimecki, W., Loh, M. M., Sugeng, A. J., & Beamer, P. (2015, October). Dietary predictors of urinary arsenic concentration for children living in a rural Arizona community. International Society of Exposure Science. Henderson, NV.
Poster Presentations
- Allen, A. M., Yuan, N. P., Wetheim, B., Krupski, L. A., Nair, U. S., & Bell, M. L. (2018, Spring). Gender Differences in Smoking Cessation outcomes Among Callers at a State Quitline. Society for Research on Nicotine and Tobacco. Baltimore, MD.
- Bell, M. L., Chen, Y., & Allen, A. M. (2019, Spring). PREVALENCE OF CIGARETTE AND E-CIGARETTE USE AMONG WOMEN WHO USED OPIOIDS DURING PREGNANCY. Society for Research on Nicotine and Tobacco.
- Yuan, N. P., Bell, M. L., Schultz, J., & O'Connor, P. A. (2017, March). Tobacco cessation among American Indian/Alaska Native individuals: The role of state quitlines in providing tailored services for this population. American Academy of Health Behaviors Annual Meeting. Tucson, AZ.