Authors
Summary
One of the main components of survey costs is interviewer call attempts associated with making contact. This paper describes an experiment conducted on a U.K. household panel study, which sought to evaluate whether an “early-bird” approach whereby participants are encouraged to contact their interviewer before fieldwork began in order to set up an appointment could increase fieldwork efficiency by reducing the number of calls required. This approach has been successfully used on the National Longitudinal Study of Youth 1979 cohort for some time but has not been evaluated experimentally. Our experiment involved two treatment groups: one group was promised a modest financial incentive (£5 per participant) to take up the “early-bird” offer and complete an interview, and the other received an appeal to their altruistic tendencies that emphasized that being an “early bird” would make their interviewer's life easier. A parallel experiment sought to evaluate the impact of differential standard incentives on response. The early-bird take-up rate was higher for the incentivized group (10 percent compared with 6 percent for the non-incentivized group) and was highest when combined with the higher standard incentive rate (17 percent). Offering both an early-bird incentive and the higher standard incentive did increase overall fieldwork efficiency, as measured by calls required per completed case, but the modest take-up rates meant that the overall impact was fairly minimal. The paper also finds indicative evidence that the early-bird offer, if sufficiently incentivized, could potentially have a beneficial impact on response rates.
Volume and page numbers
Volume: 2 , p.484 -497