Methodological issues in measuring patient-reported outcomes: the agenda of the Work Group on Outcomes Assessment.

The primary goal of the Inter-PORT work group on Outcomes Assessment is to foster methodological knowledge about the implications of various measure and design decisions for studies of the outcomes of treatment. A number of key methodological issues currently are unresolved and are in need of further study. These include: 1) the best questions to ask to assess how patients are affected by their treatments; 2) the comparative advantages of various study designs, including prospective cohorts, retrospective studies, and randomized clinical trials; 3) the way data collection decisions, such as mode of data collection and use of proxy respondents, affect study results; and 4) the best way to assess the significance of observed effects from patient, provider, and public policy perspectives. Studies conducted by the Patients Outcomes Research Teams (PORTs) are using diverse designs, measures, and data collection procedures. They provide a unique opportunity to further knowledge about methods of obtaining information about treatment outcomes. Through meetings, conferences, and publications, the Inter-PORT work group on Outcomes Assessment is trying to stimulate analyses aimed at methodological issues summarized in this paper and to ensure that new knowledge about methods is disseminated to a wide audience.