A review of EMA assessment period reporting for mood variables in substance use research: Expanding existing EMA guidelines.

Ecological Momentary Assessment (EMA) is an increasingly popular approach in substance use research for capturing reliable, in-situ, self-reported information about fluctuating variables, such as mood, over time. Current EMA guidelines do not sufficiently address the reporting of assessment periods (e.g., right now, past 30 min). Given the importance of time in EMA studies, variation and ambiguity in assessment period reporting risks misinterpretation of procedures and findings. The following study reviewed the methodological reporting of EMA assessment periods in substance use research. A search conducted in PsychINFO and PubMed using the terms "ecological momentary assessment" OR "EMA" AND "mood" AND "substance use" yielded 36 unique search results. The references of these results were hand searched and resulted in 126 additional studies. After deleting duplicates and applying inclusion criteria, 56 studies were included in the review. Review of these studies illustrated (1) variability and ambiguity in study assessment periods (2) within-study incongruence between assessment period descriptions and associated EMA prompts, (3) and a large temporal range of retrospective assessment periods across studies. Each of these findings are illustrated and discussed using examples from the literature. From these examples, assessment period reporting guidelines are proposed to improve EMA reporting clarity. Such improvements will facilitate increased synthesis of EMA research and position future researchers to investigate the validity and reliability of EMA data captured with different lengths of retrospection.