The use of monetary incentives in a community survey: Impact on response rates, data quality, and cost

Objectives. To assess the effect of incentive size on response rates, data quality, and cost in a digestive health status mail survey of a community s ample of health plan enrollees. Data Sources/Setting. The study population was selected from a database of enrollees in various health plans obligated to receive care at Park Nicolle t Clinic-HealthSystem Minnesota, a large, multispecialty group in Minneapol is, Minnesota, and the nearby suburbs. Study Design. A total of 1,800 HealthSystem Minnesota enrollees were random ly assigned to receive a survey with an incentive of $5 or $2. The response rates for each incentive level were determined. Data quality, as indicated by item nonresponse and scale scores, was measured. Total cost and cost pe r completed survey were calculated. Principal Findings. The response rate among enrollees receiving $5 (74.3 pe rcent) was significantly higher than among those receiving $2 (67.4 percent ); differences were more pronounced in the first wave of data collection. D ata quality did not differ between the two incentive groups. The total cost per completed survey was higher in the $5 condition than in the $2 conditi on. Conclusions. A $5 incentive resulted in a higher response rate among a comm unity patient sample with one mailing than did a $2 incentive. However, the response rates in the $2 condition approached the level of the $5 incentiv e, and costs were significantly lower when the full follow-up protocol was completed. Response rates were marginally increased by follow-up phone call s. The incentive level did not influence data quality. The results suggest if a survey budget is limited and a timeline is not critical, a $2 incentiv e provides an affordable means of increasing participation.