Effects of mailing strategies on response rate, response time, and cost in a questionnaire study among nurses

We conducted a pilot study to determine the most efficient mailing strategy for a postal questionnaire study among nurses in Ontario, Canada. Five mailing strategies involving types of stamps on the return envelopes were considered: no stamp, business-reply stamp, metered stamp, small regular stamp, and large commemorative stamp. We found that paper stamps, especially large commemorative stamps, on return envelopes increased the response rate and reduced the response time, as compared with other mailing strategies. Business-reply stamps had the lowest cost per response received and a low total cost.