Reminder cards Reminder postcards are sent to survey recipients roughly one week after the initial survey mailing. This card serves as a thank-you for those who responded and a reminder for those who haven't. Our experience with these cards suggests they are very helpful. Two studies provide considerable evidence of the benefit of using this approach. Type of Mail Type of mail used to distribute and receive the survey has been found to have an impact on response rates.
Certified mail seems to be helpful for a lengthy survey.
In a recent study of the impact of certified mail, varying questionnaire lengths were tested in combination with a certified mail process. The results indicated certified mail had little effect with short surveys. Express mail has also been found to positively affect response rates, especially for executives and business respondents. Though the cost of express service is much higher than regular US Mail, it can be appropriate for highly sensitive surveys where the response rate is expected to be low. Conceivably, the use of express mail conveys the importance of the survey to the potential respondent.