The effects of promised monetary incentives on attrition in a long-term panel survey

For over 35 years, a random sample of U.S. women has responded for free to a government survey that tracks their socioeconomic development. In 2003 an experiment was run to understand if providing monetary incentives of up to $40 would impact participation rates. Providing incentives to respondents, who previously refused to participate in the last survey round, significantly boosted response rates, and resulted in longer interviews and more items answered. However, providing monetary incentives to previously willing respondents showed a mixed impact on response rates, interview times, and items answered.