Background: In most countries, health care expenditures have been escalating at unsustainable rates and a growing proportion of this cost escalation has come from medical devices and other technologies. It is increasingly being recognized that the most effective way of managing health care expenditures is through the development of an organized, evidence-based health technology assessment process for the uptake, diffusion and distribution of new health technologies.

Development of an Evidenced-Based Health Technology Policy Analysis (HTPA) Process: A comprehensive process for the assessment of new health technologies has recently been established in the province of Ontario. Requests for new funding are directed through a department of the Ministry called the Medical Advisory Secretariat (MAS), who using a systematic and evidenced-based approach, provides information on the safety, effectiveness, and cost-effectiveness of the technology.

The PATH Reduction of Uncertainty through Field Evaluation (PRUFE) Iterative Evidenced-Based Framework: If it is determined that the evidentiary base for making recommendations is too uncertain, a request is made to reduce this uncertainty through the conduct of a ‘real world' Ontario-based study (called a field evaluation). The PATH reduction of uncertainty through field evaluation (PRUFE) framework is an iterative process for collecting information, updating prior knowledge and providing new evidence back to the Ministry regarding the cost-effectiveness of new health technologies.

Implications and Impact of Ontario's New HTPA Process: The Ontario HTPA process has changed the way policy makers view and use HTAs in Canada. Instead of the traditional static HTA, the new process is more relevant and responsive to the ultimate needs of decision makers and is more dynamic through an updating iterative process. In addition, since the collection of the Ontario-specific field evaluation data is inherently policy driven, the time lag for knowledge translation and uptake of the academic research findings are significantly reduced. Perhaps most importantly, the process directly addresses one of the most difficult obstacles in moving towards an evidenced-based decision making process, namely, the handling of uncertainty. The PRUFE iterative framework for reducing uncertainty has changed the nature of a HTA from a static one-time report into an iterative data collection, updating and knowledge translation process. Other provinces in Canada have begun similar assessment processes based on the Ontario model.