Female specialists were more likely to respond to a postal questionnaire about drug treatments for Alzheimer disease

OBJECTIVE: To assess demographic predictors of response for specialists who were mailed a postal questionnaire on drug treatments for Alzheimer disease. STUDY DESIGN AND SETTING: The questionnaire was sent to 317 specialists in Quebec, Canada. Demographic variables included specialty, urban/rural practice, language, sex, and 'number of years since receiving a medical license.' The specialists were stratified according to responder status (i.e., respondent/nonrespondent), and respondents were further stratified as early or late responders. Variables differing between these strata were entered into logistic regression models to see if they predicted response. RESULTS: Only 'female sex' was a predictor of response in the respondent/nonrespondent analysis (OR 2.03; 95% CI 1.17, 3.53). No demographic variables predicted early or late response. CONCLUSION: Researchers planning postal questionnaires should target male specialists with modified or additional mailings to increase response and reduce the potential for nonresponse bias. Caution should be exercised when comparing early vs. late responders as a means of assessing nonresponse bias.