Definition and yield of inclusion criteria for a meta-analysis of patient education studies in clinical preventive services.

Because selection of studies for a literature review influences conclusions, inclusion criteria are of utmost importance. For a meta-analysis of studies testing effects of patient education on preventive behaviors, we present the framework and concepts used for setting inclusion criteria for primary studies. We also present the yield in terms of number and distribution of studies that resulted from the inclusion criteria. Because we were interested in a diverse range of behaviors and a broad definition of patient education, we present a method for grouping behaviors by type of behavior change and describe parameters for subgrouping interventions by orientation and communication channel. Of 5,451 citations located and abstracts screened, 561 citations reporting potentially relevant studies were reviewed. Based on our inclusion criteria, 171 citations contained relevant studies, of which 64 studies (found in 62 citations) also met our acceptability criteria. We examine the effects of alternate inclusion criteria on the yield of primary studies and their distributions across the subgroupings. [ABSTRACT FROM AUTHOR]