GP survey response rate: a miscellany of influencing factors.

Abstract
Background. GP response to surveys is acknowledged to vary widely. The minimization of non-response bias and the generalizability of findings are fundamental research issues. Objective. The aim of this study was to identify the factors that had influenced GPs' decisions to complete a questionnaire. Methods. A short questionnaire eliciting GPs' views on minor ailment consultations was sent to 759 GPs from eight English health authorities. The response rate was 54.5%. Factors perceived by respondents to have influenced their decision to complete this questionnaire were also assessed. Subsequently, a feedback summary, together with a short evaluation form, was sent to those GPs requesting it. Results. The response from GPs located in the London area was significantly lower than that from those elsewhere. Respondents identified questionnaire length and the originating institution as the two major factors influencing their decision to return the survey. A single mailing of the evaluation form yielded a response rate of >60% predominantly positive comments. Conclusion. Many factors influence a GP's decision to complete a survey. The effect of location has, to date, largely been ignored. Furthermore, this study suggested feedback to be an important issue. Within health services research, all possible factors need to be considered to maximize response, reduce non-response bias and ultimately facilitate the dissemination of findings.