Do GPs respond to postal questionnaire surveys? A comprehensive review of primary care literature.

BACKGROUND There is a general consensus that postal surveys of physicians have low response rates. Recent systematic reviews have provided an improved evidence base to help researchers maximize response rates to self-completion questionnaires but to date, there is no comprehensive analysis of whether response rates have improved. OBJECTIVE To determine a contemporary estimate for the mean response rate to surveys of GPs published in primary care journals over the past decade. METHOD Twenty-four primary care journals from January 2000 to summer 2009 were searched for postal surveys of GPs. A total of 2838 abstracts were screened, with 683 full-text articles being examined for eligibility and 355 citations included. RESULTS Three hundred and sixty-one surveys of GPs were identified. A total of 338 598 questionnaires were distributed during the study period, with 182 256 returned response rate 61% (95% confidence interval [CI] 59-63%). There was some evidence of an association between response rate and journal impact factor, with a statistically significant higher mean response rate for journals in the highest (mean 67%; 95% CI 64-70%) compared to journals in the lowest quartile of impact factor (mean 55%; 95% CI 51-59%). There was no evidence that mean response rate had increased in the period from 2000 to 2009. CONCLUSIONS Postal questionnaires of GPs do not necessarily result in a low response rate. Response rates over the past decade appear relatively unchanged despite the greater evidence base for improving response and further work should explore reasons for this.