Supporting Public Health Policy Decision-making through Economic Evaluation: Applications and Methods

The extent to which economic evaluations of public health programs in Ontario are conducted and used by decision makers is currently very limited. This thesis supports public health decision-making through applied and methodological work. The applied work demonstrates different methods to evaluate the cost-effectiveness of public health interventions using the examples of seasonal and pandemic influenza immunization programs. The methodological component explores whether time horizon choice, one methodological consideration in economic evaluations, introduces bias. The economic evaluation of Ontario’s universal influenza immunization program (UIIP) uses primarily provincial health administrative databases to assess the impact of UIIP on health outcomes (quality-adjusted life years (QALYs), mortality), health care resource use (physician office visits, emergency department visits, and hospitalizations), and costs due to seasonal influenza. Ontario’s UIIP was found to be cost-effective compared to a targeted program.The economic evaluation of Ontario’s H1N1 (2009) mass immunization program uses a mathematical modeling approach to describe the pandemic as observed in Ontario. By removing immunization from the simulation, the impact of the program was evaluated. Outcome measures include health outcomes (attack rate, deaths, QALYs), resource use, and cost (physician office visits, emergency department visits, hospitalizations). The analysis found Ontario’s mass immunization program to be highly cost-effective despite high program cost. The methodological component investigates whether time horizon choice, a major methodological choice, introduces bias to economic evaluations. The existence, magnitude and direction of time horizon bias are demonstrated using a formal model. This work supports current guidelines in recommending a lifetime time horizon and provides a framework to discuss bias in economic evaluations. This thesis demonstrates different approaches to evaluate the cost-effectiveness of public health interventions, informs decision-making, and establishes the groundwork to guide future economic evaluations of public health interventions.