1 |
Modelling Co-Occurring and Co-Varying Reported Health Behaviours: Applications of Machine Learning and Network Psychometricsvan Allen, Zachary 27 September 2023 (has links)
Background: Health behaviours play a central role in health status and quality of life, and engaging in behaviours such as physical inactivity, unhealthy eating, smoking tobacco, and alcohol use are leading risk factors for chronic disease. However, most literature in health psychology focuses on each health behaviour in isolation, whilst everyday life experience is characterized by engaging in multiple different behaviours. The proportions of Canadians engaging in multiple sub-optimal health impacting behaviours concurrently is not well understood, nor are the interactive relationships between multiple health behaviours and health outcomes. Moving from a single behaviour to a multiple behaviour paradigm can enable a new set of questions to be answered about which health behavioural combinations people tend to engage in, and what are the strengths and directions of associations between health behaviours, questions for which we do not yet have robust answers. This dissertation aimed to advance the basic science of 'multiple health behaviours' by examining the co-occurrence and covariation of health impacting behaviours.
Methods: The thesis presents four studies that draw upon two large datasets: Studies 1, 2, and 3 use cross-sectional and longitudinal data (n = 40,268) from the Canadian Longitudinal Study of Aging (CLSA) while Study 3 and 4 use cross-sectional and longitudinal data from the international COVID-19 awareness, responses, and evaluation (iCARE) study (n = 85,861). Study 1 examines the co-occurrence of health impacting behaviours assessed with unsupervised machine learning methods, while Study 2 investigates the predictive utility of cluster analysis using multiple supervised machine learning methods. Study 3 investigates the interconnectedness of health behaviours, and their sociodemographic patterns, via network psychometrics (i.e., recursive partitioning-based network trees and network comparison tests) using cross-sectional data. Finally, Study 4 models the temporal associations between traditionally studied health behaviours and COVID-19 pandemic protective behaviours using temporal, contemporaneous, and between-subject network analysis.
Results: Cluster analysis performed with data from the Canadian Longitudinal Study of Aging revealed seven groups of people based on similarity of behaviours (Study 1). These groups demonstrated sociodemographic variation but were not stronger predictors of health outcomes than individual behaviours. This pattern was consistent across several machine learning models (Study 2). Network psychometric analysis of national and international datasets explored correlations between health behaviours and revealed generally small associations with the exception of a larger relationship between physical activity and healthy diet, while the relationship between mask use and social distancing was stronger for males then women. (Study 3). The temporal dynamics of health behaviours (e.g., physical activity, alcohol consumption) and pandemic related health behaviours (e.g., hand washing, physical distancing) were modelled with items within the iCARE survey which identified bidirectional temporal effects between outdoor mask wearing and vaping behaviour as well as a temporal relationship between outdoor mask use and healthy eating (Study 4).
Discussion: This dissertation aimed to advance the basic science of multiple health behaviours through an examination of the co-occurrence and co-variation of health impacting behaviours. Using cross-sectional and longitudinal data from the CLSA and the iCARE study, I identified seven clusters of commonly co-occurring health behaviours and their sociodemographic characteristics (Study 1), compared these clusters against individual behaviours for classifying and prediction health outcomes using machine learning (Study 2), explored the interconnectedness of traditionally studied behaviours and pandemic specific behaviours and identified sociodemographic patterning (Study 3), and modelled the temporal relationships between health behaviours over time during the Covid-19 pandemic (Study 4). In the multiple health behaviour change literature, it is assumed that health behaviours covary; however, findings from this dissertation call into question this assumption. Additionally, the lack of alignment between covariation and co-occurrence approaches for modelling the interconnectedness of health behaviours call into question the validity of cluster analysis for determining which behavioural combinations co-occur in the population. Before behavioural science can explain and predict health behaviour change, we must establish the basic science of multiple health behaviours.
|
2 |
Essays on Health Economics, Health Behaviours, and Labour OutcomesBai, Yihong January 2023 (has links)
This thesis consists of three chapters that investigate issues related to health economics, health behaviours, and labour outcomes.
Using the longitudinal data from the National Population Health Survey (NPHS), Chapter 1 examines the association between minimum wage increases and a wide range of health outcomes and behaviours, such as physical health, mental health, chronic conditions, unmet health need, obesity, insurance, smoking, drinking, food insecurity and fruit and vegetable consumption using Difference-in-Difference (DD) and Difference-in-Difference-in-Difference (DDD) models. There is no evidence that minimum wage increases are associated with most health outcomes and behaviours, including better health. There is an association for low-education females with a higher probability of reporting overall fair or poor health, and excess drinking but a lower probability of work absences due to illness and being physically inactive. For low-education men, there is an association with improved mental health and less drinking and smoking. Broadly there is more evidence that minimum wage increases lead to healthier behaviours than evidence of an actual improvement in health, perhaps because of lags effects that are not captured in this analysis.
Chapter 2 links the survey data from 2015-16 Canadian Community Health Survey (CCHS) to job characteristics from O*Net to explore the role of job characteristics in explaining the positive association between drinking alcohol and income, which is commonly found in the literature. The study finds that controlling for job characteristics reduces “income return to drinking” substantially (by between one fifth and one half, depending on gender and the measure of alcohol consumption).
Last, using data from the Ontario sample of the 2020 CCHS, Chapter 3 estimates the marginal effects of an index of social capital (at the individual or aggregated level) on changes in intentions to get vaccinated. Results show that individual-level social capital is associated with a greater willingness to get vaccinated against Covid-19 at all ages, while aggregate-level social capital is associated with higher vaccination willingness only among older adults. / Dissertation / Doctor of Philosophy (PhD)
|
3 |
UNDERSTANDING AND MANAGING CANCER PREVENTIONMcPeake, Heather 04 April 2012 (has links)
An effective population health approach to cancer prevention for young adults requires an informed understanding of cancer-relevant factors for this distinct population. Such factors include the social context, modifiable health behaviours and intrapersonal factors which influence those behaviours. It is also necessary to understand how this population seeks out and uses health information. This descriptive study was carried out through an online questionnaire delivered to a sample of 484 university students in Nova Scotia aged 17 to 29. The study revealed that most students reported good health behaviours, students new to Nova Scotia reported better health behaviours, and while health was a priority, cancer was not. Students also described how intrapersonal factors and their broader social context influenced health behaviours. The results will advance a contemporary depiction of young adult health essential for developing tailored cancer prevention and health promotion strategies.
|
4 |
Development and Validation of a Multivariable Prediction Model for All-Cause Cancer Incidence Based on Health Behaviours in the Population SettingMaskerine, Courtney January 2017 (has links)
Background: We examined if it was possible to use routinely available, self-reported data on health behaviours to predict incident cancer cases in the Ontario population.
Methods: This retrospective cohort study involved 43 696 female and 36 630 male respondents from Ontario, who were >20 years old and without a prior history of cancer, to the Canadian Community Health Survey (CCHS) cycles 2.1-4.1. The outcome of interest was malignant cancer from any site, termed all-cause cancer, determined from the Ontario Cancer Registry. Predictor variables in the risk algorithm were health behaviours including smoking status, pack-years of smoking, alcohol consumption, fruit and vegetable consumption and physical activity level. A competing-risk Cox proportional hazard model was utilized to determine hazard of incident cancer. The developed risk prediction tool was validated in the CCHS cycle 1.1 on 14 426 female and 11 970 male survey respondents.
Results: Incident cancer was predicted with a high degree of calibration (differences between observed and predicted values for females 2.97%, for males 4.23%) and discrimination (C-statistic: females 0.76, males 0.83). Similar results were obtained in the validation cohort.
Conclusions: Routinely collected self-reported information on health behaviours can be used to predict incident cancer in the Ontario population. This type of risk prediction tool is valuable for public health purposes of estimating population risk of incident cancer, as well as projection of future risk in the population over time.
|
5 |
The Burden of Unhealthy Behaviours: A Lifetime Approach Using Linked Population-Level Health SurveysPerez, Richard 10 November 2022 (has links)
The purpose of this thesis was to develop an approach that could evaluate the burden of unhealthy behaviours over a lifetime through linked population-based health surveys. The Canadian Community Health Survey (CCHS) is one such cross-sectional survey that is routinely administered to the household population and has been linked to a multitude of administrative healthcare databases. Utilizing the linked CCHS to evaluate the burden of unhealthy behaviours over a lifetime is challenging. Health behaviours naturally change over a lifetime due to many factors, and the burden of unhealthy behaviours has many different dimensions (e.g., mortality, disability, and healthcare costs) that are interconnected with each other. The degree to which lifetime disability and healthcare costs vary in relation to differences in life expectancy remains an area of debate. It is unclear whether individuals with healthy behaviours actually experience less lifetime disability and healthcare costs than individuals with unhealthy behaviours since they typically live much longer. Through several studies, this thesis developed various components that can be potentially combined into a lifetime approach which incorporates multivariable transitions.
The first two studies assessed the burden of unhealthy behaviours on period life expectancy and period lifetime healthcare costs. In the first study, CCHS-based multivariable risk algorithms were constructed to provide estimates of the causal associations between each unhealthy behavior (smoking history, leisure physical inactivity, non-active transport, leisure sedentary activity, and poor diet) and mortality. The burden of unhealthy behaviours on period life expectancy was estimated to be 7.5 (6.5-8.3) life years in 2000-2004 and 6.7 (5.8-7.4) life years in 2010-2014. The largest burdens were attributed to non-active transport and smoking. In the second study, CCHS-based multivariable risk algorithms were constructed to provide estimates of the causal associations between each unhealthy behavior and healthcare costs within different phases of life (i.e., defined by proximity to death). Unhealthy behaviours were attributed with 10.2% (2.5%-17.7%) of the period lifetime healthcare costs in 2000-2004, and 12.9% (5.6%-19.8%) in 2010-2014. Leisure sedentary activity and non-active transport were responsible for almost this entire burden, while the other unhealthy behaviours appeared to actually reduce period lifetime healthcare costs. The degree to which these estimates are accurate is unclear given the limitations of period life tables and the potential for unhealthy behaviours relating to physical activity to be a product of aging and prior illness.
The third study focused on developing methods by which to derive CCHS-based multivariable transition risk algorithms, which would allow for the creation of cohort life tables rather than period life tables. Novel methods involving multiple imputation models were utilized to create quasi-longitudinal CCHS cohorts from multiple cycles of the CCHS. These quasi-longitudinal cohorts were leveraged to develop multivariable risk algorithms for transitions towards different levels of immobility, an exposure that had been included in the prior algorithms for mortality and healthcare costs. Transitions towards moderate immobility were predicted by all unhealthy behaviours except poor diet, and transitions towards severe immobility were predicted by all unhealthy behaviours except sedentary activity. This approach can also be utilized to develop multivariable transitions for the unhealthy behaviours, which were simultaneously allowed to transition in the quasi-longitudinal CCHS cohorts. Such multivariable transition algorithms could potentially be combined with the previously derived algorithms for mortality and healthcare costs to generate more realistic estimates of life expectancy and lifetime healthcare costs. Large variability in the imputed quasi-longitudinal CCHS cohorts requires further examination, and may be reduced by including comorbidities, healthcare costs, and other information from linked administrative healthcare databases.
The last two studies evaluated the representativeness of linked CCHS respondents for population-based studies. Response and consent (to linkage) rates in the CCHS have been declining since its introduction raising concerns surrounding the comparability of CCHS samples over time. Similar to other population-based surveys, survey weights are provided that are designed address biases that may arise from non-response and non-consent to linkage. Unfortunately, these survey weights are not necessarily appropriate for many linked health outcomes that are rare. As a result, CCHS-based multivariable health risk algorithms are frequently derived from pooled unweighted CCHS samples. Fortunately, relative to wider sampling frames, unweighted linked CCHS samples were observed to be comparable over time. Nevertheless, linked CCHS respondents were observed to be healthier than comparable individuals in the community-dwelling and general populations at older ages, where they demonstrated lower risks of mortality, long-term care admission, and healthcare costs. This was not unexpected given that important segments of the population (e.g., residents of retirement homes and long-term care care) are excluded from the CCHS sampling frame. These studies highlighted the difficulties of estimating life expectancy and corresponding lifetime healthcare costs from the household population, and the necessity to ensure that such estimates realistically incorporate the time individuals may live outside of the household population over a lifetime.
These series of studies therefore resulted in mortality, healthcare cost, and transition risk algorithms that could potentially be combined to generate lifetime estimates of life expectancy, disability, and healthcare costs for a CCHS respondent. The development of transition risk algorithms requires further research. Once these methods are optimized and transition risk algorithms for all exposures of interest are generated, all the components required for this framework will be complete. At that point, explicit methods by which to combine the algorithms and validate projections will be required. This framework will enable a cause-deleted approach to be applied that simultaneously considers the impact of unhealthy behaviours on mortality, disability, transitions, and healthcare costs. This thesis represents an initial first step towards creating a framework that has the potential to generate lifetime estimates, as well as counterfactual estimates, which better reflect the complex nature of lifetime trajectories.
|
6 |
An exploration of the relationship between attitudes and expectations regarding ageing and health behaviours in older adults : a thesis portfolioMcColl, Ashley L. January 2016 (has links)
Background: With life expectancies continuing to rise and more people living beyond the age of 65, health services are under increasing pressure to provide effective care for an ageing population. Increased life expectancy increases the risk of long-term conditions like Type 2 Diabetes and cardiovascular disease that require self-management – something that poses a challenge for many people, and for older adults there may be additional barriers. Identifying modifiable factors that impede self-management is an ongoing focus in the literature; and in recent years increasing attention has been paid to the impact of individuals’ attitudes to their own ageing. Aims: The first part of this thesis portfolio is a systematic review of the literature that aims to answer the question “Are lower expectations regarding ageing associated with lower levels of physical activity in older adults?” The second is an empirical study that aims to explore the relationships between attitudes to ageing, executive function, glycaemic control and selfmanagement adherence in older adults with Type 2 Diabetes. Method: A systematic literature search was undertaken to identify studies reporting quantitative analyses of the relationship between expectations regarding ageing and physical activity. Methodological quality of the studies was appraised and synthesized, and clinical and research implications discussed. In the empirical study; 77 older adults completed self-report measures of attitudes to ageing and self-management adherence, and two brief measures of executive function. HbA1c; a biological measure of glycaemic control was also recorded for each participant. Correlations and multiple linear regressions tested the relationships between attitudes to ageing, EF, self-management and glycaemic control. Results: 8 studies (derived from 9 papers) were eligible for the systematic review, and were in consensus in their support of lower expectations regarding ageing being associated with lower levels of physical activity. The findings of the empirical study indicated that more negative attitudes to ageing in relation to physical changes predicted poorer self-management; and more negative attitudes to ageing in relation to psychosocial loss predicted poorer glycaemic control. Conclusion: The current findings are in line with an emerging evidence base supporting a relationship between attitudes to ageing, and physical health outcomes and behaviours; with more negative attitudes and perceptions of old age acting as a barrier to health promoting behaviours. Therefore, interventions targeting those cognitions could help to promote better health outcomes for older populations, as well as promoting healthy ageing and valuing older people – a current focus in policy and strategy.
|
7 |
Oral Health and Sense of Coherence : Health Behaviours Knowledge, Attitudes and Clinical StatusLindmark, Ulrika January 2010 (has links)
No description available.
|
8 |
Pregnancy Pocketbook: Improving pregnancy health behaviours in a disadvantaged communityShelley Wilkinson Unknown Date (has links)
Context Current care guidelines recommend that pregnant women receive advice about the important health behaviours which may influence pregnancy outcomes. These behaviours are associated with pregnancy-related and long-term health outcomes for both the mother and infant. Poor pregnancy outcomes can result in increased costs of health care delivery through longer hospital admissions and intensive care admissions. Although provision of behavioural advice to pregnant women is recommended, most educational materials provide limited and inconsistent information. There is a clear need for widespread delivery of evidence-based information and skill-development strategies to influence pregnancy health behaviours. One avenue of information is via the pregnancy health records (PHRs) provided by maternity health services that women carry for the duration of their pregnancy. Objective My research sought to develop, implement, and evaluate a handheld health record for use in pregnancy (the “Pregnancy Pocketbook”) in an urban population of women with a high proportion of disadvantaged women. Study Overview My research comprised two phases, a development phase, and an implementation and evaluation phase. I identified specific behaviours (cigarette smoking, fruit and vegetable intake, and physical activity) requiring intervention and reviewed evidence-based frameworks, behaviour change theories, and guidelines for the presentation of written information to support behaviour change. I developed and refined the Pregnancy Pocketbook through a number of studies. Studies 1, 2, and 3 The Pregnancy Pocketbook was refined through a qualitative evaluation of a PHR enhanced with behaviour change tools (Study 1), focus groups held with women from the target group to investigate PHR preferences (Study 2), and strategy testing of the Pregnancy Pocketbook activities with women from the target group (Study 3). The focus group results combined with those from the qualitative evaluation suggested the Pregnancy Pocketbook should be a women-held, woman-focussed resource providing essential and comprehensive information on recommended pregnancy health behaviours. It should include tools to facilitate appropriate behaviour changes and tools for women to monitor pregnancy progress and record questions and notes to facilitate communication with their health carers. Strategy testing demonstrated that the Pregnancy Pocketbook content, screening questions and activities were well received by a small sample of women, with minor changes made following testing to improve the understanding and usability of the various sections of the Pregnancy Pocketbook. The final intervention (Study 4) The final version of the Pregnancy Pocketbook was a 73-page interactive resource, designed to be used according to the 5As self-management framework (Assess, Advise, Agree, Assist, Arrange), with screening tools, information, goal setting and self-monitoring activities with information for further referral for greater support when required. It was presented in an A5 plastic ring-bound folder, with dividers, labelled ‘Your health goals’, ‘Tracking your health goals’, ‘Your first antenatal visit’, ‘Pregnancy progress’, ‘Birth summary’, ‘Glossary’, and ‘Emergency contacts and general numbers’. The Pocketbook was evaluated using a quasi-experimental two-group design. Women were recruited from two antenatal clinics within the same health service district. Women received the PP during their first antenatal clinic appointment in one clinic (PP:n = 163) and women in the other clinic received usual care (UC: n = 141). Smoking, fruit and vegetable intake, and physical activity were assessed at baseline (service entry), 12-weeks post-service-entry and 24 weeks post-service-entry. Behaviour-specific self-efficacy was also measured during pregnancy. I also assessed the PP implementation process through adherence of the staff and organisation to planned implementation processes. Results At 12-weeks post-service-entry, a significantly greater proportion of women in the Pregnancy Pocketbook (PP) group had stopped smoking (7.6% vs 2.1%), compared with the Usual Care (UC) group, p <0.05. There was a net (non-significant) increase of 5% more women meeting physical activity guidelines (PP: 1.2% increase vs. UC: 3.5% decrease) and a net 20 minute difference in median minutes of physical activity (PP: 10 minute increase vs. UC: 10 minute decrease). Both groups increased their fruit and vegetable intake. Approximately two-thirds of women reported receiving the Pregnancy Pocketbook, many without introduction or explanation. Few women completed sections of the Pregnancy Pocketbook that required health professional assistance, suggesting minimal interaction about the resource between health staff and the women in their care. Conclusion and future recommendations There were low levels of adherence to health behaviour recommendations for pregnancy in this sample. The Pregnancy Pocketbook produced significant effects on smoking cessation, even under limited delivery conditions. A refocus of antenatal care towards primary prevention is required to more consistently provide essential health information and behaviour change tools for improved maternal and infant pregnancy health outcomes. Future studies must include process evaluations and apply the theory of dissemination to enhance uptake of the interventions.
|
9 |
Investigating the Physical Activity Behaviour and Exercise Capacity of Pediatric Cardiomyopathy PatientsMoncion, Kevin 25 September 2018 (has links)
Background: Physically active lifestyles are important for health and quality of life across all stages of development. Exercise interventions have recently been incorporated as an effective strategy for adult cardiomyopathy patients, but have yet to be examined in children with cardiomyopathy. The overall goal of this pilot study was to provide preliminary data on whether there is a need to develop exercise interventions among children with cardiomyopathy. This study sought to characterize the moderate-to-vigorous physical activity (MVPA) level, submaximal exercise capacity and physical activity barriers among children with cardiomyopathy. Methods: This study employed a mixed-methods approach. Children were eligible if they were between the ages of 5 to 17 years, had a medical diagnosis of cardiomyopathy (i.e. hypertrophic, dilated, or cancer induced), atrial septal defect, or had been identified as carrying a genetic risk for cardiomyopathy. Participants were excluded if they had physical activity contraindications, had a non-cardiac medical condition or disability known to influence physical activity, or if they underwent cardiac surgery within the preceding 6 months. MVPA was assessed using 7-day omnidirectional accelerometry. Submaximal exercise capacity was determined by intermittent treadmill protocol targeting 40% to 80% of predicted maximum heart rate. Physical activity barriers were identified through semi-structured interviews, which were audio-recorded and transcribed verbatim for thematic analysis using Braun & Clark’s approach. Results: Pediatric cardiomyopathy patients (n=5) were compared to children who are genotypepositive but phenotype-negative for cardiomyopathy (n=5), children with simple congenital heart defects (CHD, n=8) and published data for Canadian children (n=1,300). Daily MVPA (48.2 ± 19.0 minutes) was variable but did not differ significantly between groups (η2=0.025, p=0.82) or from published data on Canadian children (t(17) = -1.52 p=0.15). Submaximal exercise testing revealed that children with cardiomyopathy may be able to participate in activities at moderate intensities (i.e. 4.5 ± 3.1 METs) at 150 beats per minute (bpm). Children with cardiomyopathy reported primarily disease-centred barriers to participation, including physical activity restriction and physical influences from the disease which were not reported by children who carry a genetic risk for cardiomyopathy. Conclusion: These novel data within this population group suggest that pediatric cardiomyopathy patients may have sufficient submaximal exercise capacity to participate in moderate physical activity, despite reporting disease centered barriers to physical activity. A diagnosis of cardiomyopathy may not preclude these children from achieving and healthy, active lifestyle, but their current level of participation is less than recommended for optimal health and cardiac function.
|
10 |
Associations between physical activity and posttraumatic stress disorder: a systematic review and daily diary studyGraham, Raquel 31 August 2020 (has links)
There is growing evidence to suggest an inverse association between physical activity and symptoms of posttraumatic stress disorder (PTSD). However, the mechanisms are not well understood and much of the research in this area stems from cross-sectional studies, thereby limiting what is known about these relationships at the intra-individual level. Chapter 1 of this dissertation is a systematic review examining the literature on the association between physical activity and PTSD in a variety of study designs (i.e., cross-sectional, longitudinal, and intervention). Chapters 2 and 3 used data from a 7-day diary study of 15 participants with a diagnosis of PTSD. In this study, participants completed twice daily surveys on mobile phones and wore Fitbit accelerometers measuring physical activity and sleep. Chapter 2 used multilevel modeling to examine the within-person and between-person associations between physical activity and symptoms of PTSD, sleep, positive and negative affect, and coping. Multiple operationalizations of physical activity were used (i.e., self-report and accelerometer-measured) in order to explore and better understand which metrics are most strongly related to psychosocial factors. Results from Chapter 2 add to the literature by providing evidence of within-person associations between physical activity and PTSD symptoms over the course of the day, such that on days when participants are more physically active than usual, they also report fewer symptoms of PTSD that evening. Chapter 3 discusses the utility of using N-of-1 study designs with an emphasis on the benefits of using frequent repeated measurements in clinical practice. Three case examples are presented to illustrate the intra-individual variability that is observed in symptoms of PTSD, affect, and health behaviours. These examples provide rationale for the use of intensive measurement designs in order to fully capture and understand how and when variables fluctuate over time. / Graduate
|
Page generated in 0.023 seconds