Irritable bowel syndrome: are incentives useful for improving survey response rates?

Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders. There continues to be a need for community-based research into this condition. Unfortunately, response rates in community-based IBS surveys have typically been very low. In this study, we explore the use of incentives and multiple-response options as a means of increasing survey response rates. The study was conducted in three phases. In an initial phase, no incentive was offered; in the second phase, a $5.00 incentive was offered; and in the third phase, a $20.00 incentive was offered. Response rates were higher in the incentive groups: Individual response rates were 57.9%, 72.7%, and 84.7% in the three phases, respectively. A slightly higher estimate of IBS prevalence was obtained in the nonincentive group. Selection bias is a possible explanation for this difference. A decision about whether to use incentives must be based on the specific goals of the study.