Contingent Incentives

Past research has shown that contingent incentives can be used in survey research as a way of increasing survey response rates. The concept of contingent versus noncontingent incentives is that a noncontingent incentive is given to the respondent regardless of whether the survey task is completed, whereas giving a contingent incentive is dependent on the respondent's completion of the survey task, such as completing and returning the questionnaire in a mail survey. Contingent incentives are most commonly used with phone and Internet surveys, although they can be used with any mode of [Page 145]survey data collection. Usually the researcher will use the promise of the incentive as an inducement to coax the respondent into completing the survey, because the respondent does not receive the contingent incentive unless the survey task is completed.

The most common type of contingent incentive in survey research is the monetary incentive, most often paid either in the form of cash or in the form of a check. The recent introduction of cash cards and gift cards have made this form of monetary incentive another viable option for use in surveys. Some examples of nonmonetary contingent incentives include sweepstakes entries, charitable donations, videos, gas cards, coupons, online credits, small household appliances, books, electronic devices, small gadgets or knickknacks, and so on. However, research indicates that monetary contingent incentives are more effective than nonmonetary incentives of the same value.

Contingent incentives have generally been found to be less effective than noncontingent incentives for completing a survey. This often is the case even when the contingent (promised) incentive is several times larger in value than the noncontingent incentive given to a respondent before she or he completes the survey task. However, in some situations, it is impractical to offer a noncontingent incentive. Normally a noncontingent incentive would be offered in a situation in which there is an easy way to deliver it at the same time as the survey instrument, such as in a mailed survey. In contrast, the contingent incentive is, by definition, given after the survey task is completed. How soon after this is promised to take place will also affect the power of the contingent incentive to raise the response rate. The sooner the contingent incentive is given to the respondent after she or he completes the survey task, the greater its power to raise response rates. With telephone and in-person interviews, a contingent incentive can be a strong persuader for the interviewer to use to gain cooperation. However, in the case of a telephone survey, gratification in receiving the contingent incentive is delayed, unlike an in-person interview in which the incentive can be given immediately after the survey task is completed. Similarly, a monetary contingent incentive paid in cash provides more immediate gratification than one paid via check or cash card. Thus, contingent incentives paid in cash immediately upon completion of the survey task are likely to have the greatest positive impact on raising responses rates compared to contingent incentives of the same value that are given after some lag in time and/or are not given as cash.

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