Evaluating the utility of administering a reaction time task in an ecological momentary assessment study

Rationale: Cognitive processes underlying drug use have typically been assessed in laboratory settings. More detailed and ecologically valid data may be possible if assessments were conducted in an ecological momentary assessment (EMA) setting. Objectives: We evaluated the feasibility and utility of administering a reaction time task on a hand-held computer (personal digital assistant, PDA) in an EMA setting. Materials and methods: Twenty-two smokers and 22 non-smokers carried around the PDA for 1 week as they went about their daily lives. They were beeped at random times four times per day (random assessments, RAs). Participants were also instructed to press an "anxiety assessment" (AA) button on the PDA whenever they felt suddenly anxious. At each assessment (RA, AA), participants responded to items assessing subjective, pharmacological, and contextual variables, and subsequently completed a Stroop task (classic-Stroop, emotional-Stroop, or smoking-Stroop task). Results: Participants responded to 81.2% of RAs, completed assessments in an average of 4.44 min, reported no interruptions on the majority of assessments (62.4%), and produced data with adequate reliability. Using generalized estimating equation (GEE) analyses, age was associated with the classic-Stroop effect, state anxiety was associated with the emotional-Stroop effect, and Fagerstrom Test for Nicotine Dependence scores were associated with the smoking-Stroop effect. Conclusions: The study provided evidence for the feasibility and utility of the approach.