Visible Cash, a Second Incentive, and Priority Mail? An Experimental Evaluation of Mailing Strategies for a Screening Questionnaire in a National Push-to-Web/Mail Survey.

In push-to-web surveys that use postal mail to contact sampled cases, participation is contingent on the mail being opened and the survey invitations being delivered. The design of the mailings is crucial to the success of the survey. We address the question of how to design invitation mailings that can grab potential respondents' attention and sway them to be interested in the survey in a short window of time. In the household screening stage of a national survey, the American Family Health Study, we experimentally tested three mailing design techniques for recruiting respondents: (1) a visible cash incentive in the initial mailing, (2) a second incentive for initial nonrespondents, and (3) use of Priority Mail in the nonresponse follow-up mailing. We evaluated the three techniques' overall effects on response rates as well as how they differentially attracted respondents with different characteristics. We found that all three techniques were useful in increasing the screening response rates, but there was little evidence that they had differential effects on sample subgroups that could help to reduce nonresponse biases.