Engagement begins at recruitment: Comparing videoconference verification to passive online screening for participant retention and study engagement.

Researchers who conduct studies online increasingly struggle with fraudulent respondents, programmable bots, inattention or carelessness, and ineligible impostors. This study tested whether participants in a longitudinal intervention study who were recruited using videoconference eligibility verification-meeting participants one by one on Zoom to verify their identities-were more engaged in the study tasks and showed better longitudinal retention. Using existing data from a sample of Canadian young adult women (N = 1257), we compared participants who were screened via videoconference to participants who were passively screened (i.e., possessed valid e-mail addresses) and participants who were pre-screened members of a commercial participant platform (Prolific.com) on seven measures of retention and six measures of engagement with study tasks. Results showed that videoconference-verified participants had better rates of study initiation and retention, with over 90% completing all study waves. However, we found no meaningful differences between recruitment streams as a function of time to survey completion, engagement with the study's intervention activities, or honest responding. Videoconference eligibility verification may be a practical tool for recruiting participants likely to remain enrolled in longitudinal research and limit attrition.