Objective: To qualitatively determine factors that are associated with higher participation rates in community-based health services research requiring significant physician participation burden.
Measurements: A review of the literature was undertaken using MEDLINE and the Social Science Research Index to identify health services research studies that recruited large community-based samples of individual physicians and in which the participation burden exceeded that of merely completing a survey. Two reviewers abstracted data on the recruitment methods, and first authors were contacted to supplement published information.
Main results: Sixteen studies were identified with participation rates from 2.5% to 91%. Almost all studies used physician recruiters to personally contact potential participants. Recruiters often knew some of the physicians to be recruited, and personal contact with these "known" physicians resulted in greater participation rates. Incentives were generally absent or modest, and at modest levels, did not appear to affect participation rates. Investigators were almost always affiliated with academic institutions, but were divided as to whether this helped or hindered recruitment. HMO-based and minority physicians were more difficult to recruit. Potential participants most often cited time pressures on staff and themselves as the study burden that caused them to decline.
Conclusions: Physician personal contact and friendship networks are powerful tools for recruitment. Participation rates might improve by including HMO and minority physicians in the recruitment process. Investigators should transfer as much of the study burden from participating physicians to project staff as possible.