Mail Survey Prenotification Letters

Many researchers have studied prenotification letters to determine if they increase response rate. A meta-analysis of these studies revealed an aggregate increase in response rate of 7.7 percent. Prenotification letters might help to establish the legitimacy of a survey, thereby contributing to a respondent's trust. Another possibility is that a prenotification letter builds expectation and reduces the possibility that a potential respondent might disregard the survey when it arrives.

Pre-letters are seldom used in marketing research surveys. They are an excellent (but expensive) way to increase response. The researcher needs to weigh the additional cost of sending out a pre-letter against the probability of a lower response rate. When sample sizes are small, every response really counts and a pre-letter is highly recommended.

1. Briefly describe why the study is being done and identify the sponsors. This is impressive and lends credibility to the study.

2. Explain why the person receiving the pre-letter was chosen to receive the questionnaire.

3. Justify why the respondent should complete the questionnaire. The justification must be something that will benefit the respondent. For most people, altruism is not sufficient justification. If an incentive will be included with the questionnaire, mention the inclusion of a free gift without specifically telling what it will be.

4. Explain how the results will be used.