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.
Master's Student Supervision (2010 - 2018)
Background: Uncertain outcomes are an unavoidable fact of medicine. First-order uncertainty (e.g. “10 in 100 people can expect an outcome in the next year”) has well-established guidelines as to how it should be best presented, but it is not clear if and how to present second-order uncertainty, referred to as ambiguity (e.g. “10 [95% CI 5,15] in 100”).Objectives: To explore the ways in which ambiguity in risk is currently being described to patients by (1) identifying existing presentation techniques and evidence for their potential impact on decision-making, (2) investigating how presentation techniques influence decision-related outcomes, including intention, trust, worry, decisional uncertainty, risk perception, knowledge and preference, and (3) determining which techniques should be investigated further.Methods: The literature on current techniques to present ambiguity was systematically reviewed through an electronic search of the Medline/PubMed database, and an existing database of patient decision support interventions. The influence of each identified communication technique was evaluated by the design and implementation of a web-survey in a hypothetical atrial fibrillation vignette.Results: Nine distinct presentation techniques were identified as having been used in the past, and were shown to influence decision-making outcomes. Of these techniques, the visual and textual range techniques were found to result in change in intention (in both directions) which was statistically significant, while other techniques decreased trust, increased decisional uncertainty, and resulted in greater knowledge.Conclusions: Techniques that resulted in the worst knowledge of the range in risk scores tended to be the ones that were preferred by participants. Yet, without good knowledge of risks involved with different medical options, informed consent, and value-based decisions are challenging. Findings from this work indicate that some techniques for presenting uncertainty, such as the visual and textual range techniques, impact various psychometric outcomes related to decision-making, including intention to take oral anticoagulation, trust in risk estimates, decisional uncertainty and knowledge of ambiguity. Further research should focus on testing the influence of these techniques on decision-making related outcomes.
Background: Patient decision aids (PtDAs), tools used to facilitate shared decision-making, help improve patient-physician communication and the quality of healthcare decisions. Over 500 PtDAs are available, yet implementation of these tools has been limited. In order for decision-makers to implement new health care interventions such as PtDAs, they require rigorous economic evidence demonstrating that such interventions provide value for money.Objectives: To explore the economic consideration of PtDAs by (1) systematically reviewing PtDA trials that have evaluated economic outcomes, (2) exploring the potential cost-effectiveness of a PtDA for individuals with obstructive sleep apnea (OSA), and (3) describing the development of a an OSA PtDA prototype.Methods: PtDA trials evaluating economic outcomes were systematically reviewed through an electronic search of Medline/PubMed, Embase, CINAHL, and PsycINFO databases. The potential cost-effectiveness of a PtDA for OSA was evaluated through a Markov cohort decision-analytic model, which explored the cost-effectiveness of a PtDA compared to usual care. Finally, an OSA PtDA prototype was developed according to the International Patient Decision Aid Standards (IPDAS) criteria.Results: Our systematic review found that PtDAs will likely increase upfront administration costs, but may decrease short-term costs by reducing the uptake of invasive treatments. Most studies did not comprehensively capture long-term costs and health outcomes appropriately. Through our economic modelling of a PtDA for OSA we found it could be a cost-effective use of resources provided it increases adherence to treatment. However there was considerable uncertainty in this estimate, with expected value of information analysis revealing that additional research is warranted. We developed and tested a prototype OSA PtDA, and found no evidence that users became stuck or experienced errors during usability testing. The majority of users found the PtDA easy to use and worthy of recommending to others.Conclusions: Policy-makers lack sufficient economic evidence to make informed decisions about whether and where to invest in PtDAs. This evidence gap could be a factor contributing to the slow implementation of PtDAs. Using OSA as a case study, this work demonstrates an economic modelling framework that can be used to evaluate the potential cost-effectiveness of PtDAs.