Health Technology Assessment of Medical Interventions in the Prevention and Treatment of Disease: Directions of Further Research and Policy Implications

textabstractHealth technology assessment (HTA) originated from the spread of costly medical equipment and growing concerns over the ability and willingness of taxpayers and health insurers to pay for them. The main aim of HTA is to provide a range of stakeholders, typically those involved in funding, planning, purchasing, and investing in healthcare, with accessible, useable, and evidence-based information that will guide decisions about technology and the efficient allocation of resources. The present thesis addresses some of the methodological challenges of the health technology assessment and evaluates the impact of economic evaluations in healthcare decision-making process. Systematic reviews have a central role in evidence based-medicine. The quantitative systematic review, also known as meta-analysis provides a logical structure for quantifying the existing evidence. Meta-analysis offers the opportunity to critically evaluate and statistically combine results of comparable studies or trials. The aim is to get a consistent estimation of the global effect of a procedure on a specified outcome by increasing the number of observations and statistical power. This thesis presents the results of a systematic literature review with meta-analysis on the effectiveness of lifestyle intervention in the prevention and treatment of obesity. The systematic review provides new information on the effectiveness of lifestyle interventions by assessing the mid- to long-term effects on weight and cardiovascular risk profile in overweight and obese people. Patient reported outcomes provide the patient perspective on the effectiveness of treatment. This thesis presents the data collected from a study that establishes the validity of the electronic versions of three quality of life measures in comparison to the existing paper versions. For health technology manufacturers it is important to provide evidence of the validity of the quality of life instruments in the electronic format as compared to paper version. Mathematical modeling is used widely in economic evaluations of medical interventions. Health economics models represent an important analytic framework to generate estimates of cost-effectiveness. We addressed the modeling challenges in two decision analytic models developed to inform decision-making process. One model presents the development and results of a cost-effectiveness model of zoledronic acid versus risedronate in Paget’s disease of bone. The second model presents the development and results of an economic analysis that evaluates the lifetime effects of three-year lifestyle intervention in the prevention and treatment of obesity. The model estimates the cost-effectiveness of lifestyle intervention versus standard treatment in overweight and obese people in Switzerland. The importance of health economics research utilization in policy-making and of understanding the mechanisms involved is increasingly recognized. The existence of relevant research, though necessary, is not sufficient. Evidence-based policy is difficult to achieve and it is widely agreed that health policies do not reflect research evidence to the extent that in theory they could. In this thesis we assessed the use of research evidence relating to economic analyses in healthcare decision-making. We conducted a literature review to summarize and synthesize published literature on self-reported attitudes of healthcare decision-makers towards economic evaluations of medical technologies. The aims of this literature review was to determine the extent to which economic evaluations are used in health policy decision-making, and to consider factors associated with the utilization of such research findings. Examination of the policy-making process confirms it to be complex, with man! y genuine obstacles to evidence-based policy-making at the same time as there are factors that could increase research utilization