Comparing Reported Prescription Drug Misuse between Ecological Momentary Assessment versus Timeline Follow-Back among College Students.

Accurate assessment of prescription drug misuse (PDM) is critical among young-adult college students, a particularly high-risk group for this substance behavior. No studies have compared assessments of college students' reports of PDM obtained from their reporting in daily life (via ecological momentary assessment; EMA) to their retrospective accounts of PDM over the same period (via timeline follow-back interview; TLFB), an approach that is commonly used in substance use research. / To determine day-level agreement and person-level agreement in college student reports of PDM in EMA versus TLFB methods. Participants were 297 college freshmen and sophomores (69% female) recruited based on misuse behavior in the past three months. PDM behaviors were captured in daily life using EMA for 28 days and TLFB administered during an in-person lab visit. Agreement was assessed at the person level (any PDM during the 28 days) and day level (PDM on a given day) using Cohen's kappa and percent agreement. PDM was reported more frequently using TLFB compared to EMA. Person-level agreement between the two methods was good (k = 0.62, 95% CI: 0.53, 0.70), whereas day-level agreement was fair (k = 0.23, 95% CI: 0.19, 0.28). Agreement in stimulant misuse reported across methods was more consistent compared to reports of other medication classes. Findings offer implications for the assessment of college student PDM data in substance use research.