Incentive effects on cooperation rates and sample composition in the alcohol and drug services study

Abstract

In the past, incentive payments have proven successful in increasing survey response rates. In particular, incentives have been shown to increase the yield rate for harder-to-interview respondents. Despite this success, incentives are not without controversy. Opponents note that incentives may make the survey appear less important, destroy civic responsibility, and create an unnecessary expectation. Over time researchers may have to pay sizable incentives to achieve the response rates obtained 20 years ago before the use of incentives was common. Incentives could also have a detrimental impact on sample composition. The Alcohol and Drug Services Study (ADSS) included an incentive payment sub-study as part of its client follow-up phase. The sample for this sub-study randomized clients into four groups. One group was paid $25, the amount received by other responding clients in the ADSS main study. Respondents in the other three groups were paid an alternative amount (i.e., $0, $10, or $35). In examining the impact of varying incentives to sampling benchmarks, such as response rate and sample composition, the ADSS incentive sub-study found that the fears of opponents concerning the use of incentives were substantially unfounded, at least among the substance abuse treatment clients in the follow-up phase of ADSS.