Relevant Degree Programs
Graduate Student Supervision
Doctoral Student Supervision (Jan 2008 - May 2019)
Background: Supporting shared decision-making (SDM) between patients and providers is a key health care objective. SDM-interventions can help encourage SDM but may require investment. This thesis used a case study of treatment decision-making for advanced osteoarthritis to quantify the economic value of SDM-interventions in health care. Methods: A trial-based cost-effectiveness analysis and a longer-term cost analysis using administrative data was undertaken to estimate the value of a SDM-intervention in adults considering total joint arthroplasty. Limitations of conventional cost-effectiveness analysis in assessing the consequences of SDM-interventions were outlined, and methods for valuing the process of SDM presented. A systematic review of discrete choice experiments (DCEs) that have valued the process of SDM was undertaken. A two-step chained valuation technique which included a DCE was completed to estimate the health state utility value of the process of SDM.Results: The trial-based cost-effectiveness and administrative data analyses suggested that SDM-interventions for total joint arthroplasty provided value, resulting in lower costs at two and seven-years follow-up and similar quality-adjusted life-years (QALYs) over the two-year trial period. QALYs may fail to capture the consequences of SDM-interventions, such as the value of being informed and involved in decision-making. To reflect the opportunity cost of allocating scarce resources toward these non-health benefits, Canadian guidelines suggest that their value be ascertained through the trade-off with health outcomes using societal preferences. The systematic review found 25 studies that have valued SDM using a DCE. No studies valued SDM in advanced osteoarthritis, and most did not include a health outcome attribute or elicit societal preferences. Analysis of the data from the DCE completed by nearly 1,500 Canadians aged 60 and older revealed that respondents were willing to sacrifice health outcomes for greater SDM and estimated the value of SDM.Conclusions: Evidence suggests that SDM-interventions for adults with advanced osteoarthritis are a cost-effective use of resources. Results from the trial-based cost-effectiveness analysis, systematic review, and DCE suggest that policy-makers may be justified in allocating scarce resources toward SDM-interventions at the expense of other interventions that provide health benefits. Future research is required to quantify the value of SDM-interventions in other contexts.
Background: Shared decision-making (SDM) has been suggested as a means to improve communication between patients and their healthcare providers, with the purposes of improving multiple asthma-related health outcomes. Despite mounting evidence that suggests potential benefits attributable to SDM, clinical uptake has been slow. Objectives: The purpose of this dissertation is to ascertain the role of SDM in asthma management, to determine the extent to which SDM is currently being implemented into regular asthma care, and to suggest clinical implementation strategies that may facilitate SDM implementation in BC.Methods: This project consists of a) a systematic review of physician attitudes toward SDM, b) a comprehensive narrative literature review to describe the proposed role of SDM in asthma, c) a population level analysis to explore variation in adherence to controller medication, as well as d) an online survey of 117 adult asthma patients living in BC. Results: Results of this work show that in general a) physicians support the use of SDM in various clinical practice scenarios, b) there is a clear role for SDM in treating asthma patients with the goal of reducing the burden of controller medication non-adherence, and c) adherence to controller medications is sub-optimal, with little variation being explained at the population level. The patient survey (d) provided additional insight into this research agenda by showing that while patients prefer to be actively involved in treatment decision-making, there is substantial variation in the extent to which asthma patients are being engaged in their care. Furthermore, multiple predictors of adherence that can be addressed during the clinical encounter (e.g. medication-related concerns) were shown to impact self-reported treatment adherence. Conclusions: The results of this project provide further support for the use of SDM in regular care of asthma patients. I conclude by highlighting the importance of addressing issues related to adherence in an individual and ongoing basis, the value of increasing awareness about the use of SDM, and the potentially valuable role of engaging non-physician caregivers in future SDM implementation efforts. These findings may guide future research investigations regarding SDM uptake and efforts to reduce the disease burden of asthma.
Background: Reducing the burden associated with asthma and chronic obstructive pulmonary disease (COPD) requires addressing challenging care gaps. Mathematical decision-analytic models are among the best tools to address such challenges. Objectives: My overall aim in this thesis was to identify cost-effective treatments in asthma, and to quantify the value of personalizing treatments in COPD. These goals led to four specific objectives: 1) To inform the economic and health impact of improving adherence to the standard controller medications in asthma; 2) To assess the cost-effectiveness step-up treatment options for severe asthma patients; 3) To build a framework for individualized prediction of lung function in COPD; and 4) To quantify the value of personalizing COPD treatments. Methods: Cohort-based models were used to quantify the benefit of improving adherence to controller medications and evaluating the cost-effectiveness of treatments for severe asthma. Mixed-effects regression with external validation was undertaken to project lung function decline up to 11 years for COPD. Microsimulation was used to fully incorporate disease heterogeneity to evaluate the return on investment from individualizing treatments in COPD. All modeling studies were based on careful evidence synthesis and original data analyses whenever required. Results: Improving adherence to controller medications in asthma results in a gain of 0.13 quality-adjusted life years (QALYs) at the incremental cost of $3,187 per patient over 10 years. Even with full adherence, 23% of patients would remain uncontrolled. For this group, the addition of bronchial thermoplasty was associated with an incremental cost-effectiveness ratio of $78,700/QALY. Clinical variables explain 88% of variability in lung function decline. The efforts towards individualizing treatments based on patients’ clinical traits would be associated with an additional $1,265 net benefit per person. Conclusion: The analyses in this thesis demonstrate the value of mathematical simulation models in evaluating the outcomes of policies and scenarios. It is unlikely that any empirical research per se would be able to provide the insight generated in this thesis regarding the identified care gaps. Mathematical models can not only be used to evaluate the outcomes associated with specific interventions, but also to objectively document the return on investment in personalized medicine.
Demand for health services is growing, but funding is often failing to keep pace. To ensure that budgets are balanced and that delivered services continue to be high quality, decision makers are having to set priorities, removing funding from some services- this is disinvestment. This thesis details research incorporating a literature review followed by a two stage empirical investigation into the way that disinvestment decisions are made and whether or not the public should be involved. The first stage is a Q-Methodology study, the second is in-depth interviews. The population for the study is NHS health professionals (including managers and clinicians). 55 participants took part in the Q-study, and of these, 20 took part in follow-up interviews. The study highlighted three distinct perspectives, all of which supported public involvement. One was unequivocal in its support, another highlighted some potential disadvantages to involving the public and the third suggested that the public should have the freedom to choose whether they became involved. The follow up interviews re-iterated participants’ support for involvement but suggested that the public should become involved earlier and to a greater extent in those disinvestment decisions which affected more patients and/or resulted in a tangible loss of services.