College students' momentary stress and prescription drug misuse in daily life: Testing direct links and the moderating roles of global stress and coping.

Prior survey-based research has documented associations between greater levels of stress and increased prescription drug misuse behaviour. These studies uniformly rely on assessments of both the stress experiences and the substance behaviour after they occurred (commonly spanning 6-12 month retrospective timeframes). Less is known about the extent to which variations in momentary stress predict the actual occurrence of prescription misuse in daily life among college students with elevated risk for engaging in the behaviour. In this study, 297 participants (69% females; M age  = 19.5 years, SD age  = 0.71) completed a 28-day ecological momentary assessment procedure that collected self-reported stress and other contextual experiences in moments preceding prescription drug misuse. Analyses tested the within-person association between momentary stress and prescription drug misuse and examined the extent to which the relation between stress and misuse was moderated by participants' assigned sex or global stress and coping levels. Results from hierarchical generalised linear modelling indicated a significant within-person association between momentary stress (i.e., higher than usual relative to one's own mean) and greater likelihood of prescription misuse in daily life, accounting for the number of stressors and timing covariates. No significant moderation by participant sex was found, and moderation effects by global stress and coping levels were not in the expected directions. Direct results highlight the role of momentary stress experiences on health-relevant substance behaviours and provide future directions for research and applied efforts.