Survey research is a widely used method for collecting data about a population of interest. A high survey response rate mitigates concerns about non-response bias and is thus a significant component for the validity of survey-based findings. At the same time, response rates to surveys have been in general decline in recent decades, and survey data are increasingly collected online using web-based questionnaires. Although online surveys comprise a relatively fast and inexpensive way to collect information from people, this development amplifies the problem of low response rates: The response rates in online surveys are typically lower than those in surveys using other data collection methods (i.e., postal questionnaires and face-to-face interviews).
Identifying the strategies that investigators may use to maximize survey response rates in online surveys is thus important. While survey researchers have examined a range of strategies for increasing survey response rates, one particular approach appears to be understudied: The use of a video in the survey invitation email.
This study examines the effects of two video treatments on participation in a nation-wide online survey among Danish parents. During a trial period of two months, a sample of Danish parents to a child (aged 9 months, 24 months, or 36 months) receive an email invitation to participate in an online survey. Both parents of 15,000 children—5,000 in each child age group—will be invited to participate (30,000 parents). Clustered at the child level, each parent couple is randomly assigned to either a control group (no video) or one of two treatment groups (standard or enhanced video). Parents in the treatment groups receive the same email invitation as those in the control group—with one important exception: The email includes a link to a short informational video. The video shows an investigator explaining the purpose of the survey and the prosocial value of the individual’s participation, thus seeking to elicit participation by personifying the task of survey response and increasing perceived task significance. The two video treatments differ in terms of visual content: A “standard” video treatment simply shows the principal survey investigator (low cost), whereas the “enhanced” video treatment involves a set of cover shots meant to supplement and visualize the audio content (high cost). We examine and compare the effects of the video treatments on the survey response rate, response speed, survey dropout rate, survey completion time, survey response patterns, and participation in subsequent survey waves. We also test for heterogeneous effects by socioeconomic characteristics (parent’s sex, ethnicity, age, and educational attainment; child’s sex, age, and “at risk” status).