Who Participates in Focus Groups? Diagnosing Self-Selection

Focus groups have become increasingly popular in political science alongside the growth in field experimental and other causal inference-oriented work in comparative politics. Yet, scholars rarely provide details about recruitment processes and descriptive statistics on focus-group participants. This situation is problematic given the likelihood of self-selection and the fact that scholars often use focus groups to pretest or refine experimental treatments or survey questionnaires. By leveraging a series of focus groups that were recruited from a pool of large-N survey respondents, this article demonstrates a method for assessing which variables drive the decision to participate. I recommend that scholars diagnose self-selection into focus groups whenever possible; that they compare participants to relevant baselines when working with samples of convenience; and that they always provide descriptive statistics and details on how focus-group members were recruited.