Objectives: Since 1997, members of the International Network of Agencies for Health Technology Assessment (INAHTA) have collaborated on a Joint Project to track the diffusion, evaluation, and clinical policy of positron emission tomography (PET). Part 2 of this updated Joint Project report summarizes HTA-based strategies for directing the clinical use of PET and a discussion on the value of HTA in managing the diffusion of high cost diagnostic technologies, which were presented at an INAHTA-sponsored workshop at the Health Technology Assessment International Annual Meeting in 2004 on strategies for managing high cost diagnostic technologies.

Methods: A summary of the workshop proceedings is presented.

Conclusions: Sharing assessment work, universal agreement in assessment conclusions, stakeholder input, and modeling techniques help manage the uncertainty in the evidence base while targeting clinical use of PET toward the most promising indications. Emphasis on HTA findings, linkage between financing of clinical PET and outcome evaluation, and targeted dissemination of scientific findings empower providers to reduce unnecessary utilization and contain costs within a quality improvement framework. Above all, a trustworthy source of HTA information and a process that is conducive to using scientific evidence as the basis for decision making are essential for managing the diffusion of complex and costly diagnostic technologies in patient care.

Objectives: The International Network of Agencies for Health Technology Assessment (INAHTA) has been tracking activities associated with the clinical use of positron emission tomography (PET) in its members' healthcare systems since 1997 and published its first Joint Project report on PET in 1999. Part 1 of this Joint Project report presents survey results on diffusion, assessment activities, and policy for clinical use related to PET among INAHTA members since 1999.

Methods: INAHTA members were surveyed in 2003–2004.

Results: Twenty-seven INAHTA agencies (69 percent response rate) from nineteen countries responded to the survey. Dedicated PET systems are the most universally installed systems to date. Mobile scanners and modified gamma cameras are used occasionally as lower cost alternatives, and interest in PET–computed tomography hybrid models is rising despite limited assessment of impact on service planning. PET was used and assessed most commonly for managing patients with cancer. All respondents reported having some form of public funding for clinical PET frequently linked to data collection for the purpose of gathering evidence to refine clinical use and guide resource allocation toward indications that maximize clinical and cost-effectiveness.

Conclusions: The use of HTA within a continuous quality improvement framework can help optimize scarce resources for evaluation and use of high cost diagnostic technologies such as PET, particularly where potential clinical or cost-effectiveness is considerable but conclusive evidence is lacking.