A Multisample Demonstration of Using the Prolific Platform for Repeated Assessment and Psychometric Substance Use Research

The Prolific platform offers a potentially useful and efficient crowdsourcing option for repeated assessment substance use research, including for psychometric research requiring large samples. We present both (a) a series of practical recommendations for using Prolific and (b) data from multiple samples demonstrating Prolific's potential for efficiently collected repeated measures data. First, we present data from a 5-day daily diary protocol. We recruited a large sample (N = 321 at Day 1) screened for a history of self-identified mental health issues and weekly alcohol use. Participant adherence was good (82%) even without in-person contact. Alcohol use patterns conformed to theoretical expectations: Participants were more likely to drink on Fridays and Saturdays than other days, men drank more than women, and higher Alcohol Use Disorders Identification Test (AUDIT; Saunders et al., 1993) scores were associated with an increased likelihood of use and more overall drinking on a given day. Second, we present data from 429 Prolific participants screened for a history of mental health issues who completed assessments 2 weeks apart with strong retention (N = 377; 88%). We compare these data with the data from undergraduates (N = 529) to demonstrate Prolific's utility for conducting psychometrically oriented substance use research. Internal consistency estimates for measures from the Prolific data matched or exceeded those from the undergraduate data. Furthermore, measure scores showed strong temporal stability, and factor structures (e.g., AUDIT item-level structures) conformed to theoretical expectations. Collectively, these findings indicate that Prolific can be used successfully for repeated measures data collection. Public Health Significance We provide recommendations and data analytic examples showing how the online crowdsourcing Prolific platform can be used to efficiently collect longitudinal data from large samples of participants varying in their substance use and mental health histories. Our demonstrations indicate that Prolific can be used successfully for (a) studying how factors such as mood and interpersonal difficulties are associated with substance use over time and (b) improving how researchers assess substance use and mental health issues.