The Effect of Non-Monetary Incentives on Unit and Item Non-Response in Surveys on Intimate Topics
The use of noncontingent incentives constitutes a well-established technique in order to reduce both item- and unit-nonresponse in self-administered surveys. While the current state of research clearly indicates that monetary incentives included in the initial mailing should be the method of choice, the use of nonmonetary incentives might be more appropriate in at least two situations: Depending on the study area, various regulations on data protection or budget restrictions might prohibit researchers from sending multiple follow-up reminders as suggested in Dillmans' Total Design Method (TDM). Current research indicates that low-value nonmonetary incentives can serve as a substitute for the absence of follow-up mailings to a certain degree. Secondly, the use of monetary incentives might be disadvantageous in interaction with certain survey-topics (e.g. topics that correspond to reciprocity, morality or other social desirable norms as well as intimate questions) and might even turn out to provoke reactance on the respondent's side.
The contribution renders the adequacy of nonmonetary incentives under these two conditions and presents the results of an experimental designed study. Within a German sample of 4000 target respondents, who received a survey on "Morality and Conscience in modern life", the initial mailing of a ball pen showed significant effects on the following criteria:
- Response rate (unit-and item-non response) and response-speed
- Data Quality (Elaborateness of answers to open-ended questions and Reduction of Acquiescence Response Patterns)
The findings suggest that the use of low-value nonmonetary incentives is a cost efficient strategy to improve data quality, especially in the context of intimate or personal topics. Because of their more subtle character, small gifts may even be more appropriate than cash- or money-related incentives in certain contexts.