Impact of a postcard versus a questionnaire as a first reminder in a postal lifestyle survey.

STUDY OBJECTIVE The study aimed to consider the impact of two different types of reminder on response rates and costs in a postal survey. DESIGN The study was a cross sectional survey. A self-completion lifestyle questionnaire was used. Those who did not respond after the initial mailing were randomly allocated to receive either a postcard or questionnaire as a first reminder. All outstanding non-responders received a questionnaire as a second reminder. SUBJECTS A representative sample of 698 adults aged 16-70 was used, drawn from a family health services authority register. MAIN RESULTS Postcard reminders were as effective as questionnaire reminders in increasing response whether one or two reminders are sent. The costs per response were calculated. Two questionnaires as reminders were found to be 1.7 times more expensive than a postcard plus questionnaire. Including the initial mailing, the cost per response using all questionnaires was 1.3 times the cost when a postcard was used for the first reminder. CONCLUSIONS To increase the response to a postal survey effectively and economically, two reminders should be sent--first a postcard and then a questionnaire.