Context-based evidence-based decision-making: Case study of evidence utilisation in the development of cancer screening policy

This thesis examines the impact of the decision-making context on the determination of what constitutes evidence and how that evidence is utilised in the development of health policy. Four cases were studied where expert groups were tasked with developing cancer screening policy recommendations for either breast, cervical, colorectal or prostate cancer in Ontario, Canada.; A conceptual framework for evidence-based health policy was developed based on a process model of utilisation, consisting of three stages, including the introduction, interpretation and application of evidence. The decision-making context was divided into both an internal (where decision is made) and an external (where decision is applied) context, to more clearly distinguish how context can impact on evidence utilisation. Qualitative methods were employed to determine the nature of the evidence, the key components of both the internal and external decision-making contexts and how evidence was utilised for each of the four cases studied.; Analysis of the empirical data led to refinement of the conceptual framework to better explain how the decision-making context impacted on evidence utilisation. Rather than a single three-stage process model of evidence utilisation, the process could be better described by three distinct phases, addressing efficacy/effectiveness (can/does it work?), feasibility (should we do it here?) and implementation (how do we do it here?) issues. Evidence hierarchies and stakeholder representation were the two main methods employed by the expert groups to utilise evidence. Evidence hierarchies focused attention on the quality of evidence, and were most appropriately applied to efficacy/effectiveness issues where experimental evidence was more likely. Stakeholder representation did not provide a clear mechanism for assessing the quality of evidence but did allow greater consideration of external contextual factors, which facilitated the assessment of the generalisability of evidence, making stakeholder representation more appropriate for assessing feasibility and implementation issues.; The development of health policy needs to recognise the distinct features of each phase and the relative strengths and weaknesses of the two methods of evidence utilisation. This will allow a broader conception of evidence and encourage more active assessment of the generalisability of evidence while maintaining an appropriate focus on the quality of evidence.