Examining reactivity to intensive longitudinal ecological momentary assessment: 12-month prospective study.

Purpose: To examine the association between intensive, longitudinal ecological momentary assessment (EMA) and self-reported eating behaviors.

Methods: Secondary analysis of the EMPOWER study-a 12-month observational study that examined the microprocesses of relapse following intentional weight loss using smartphone-administered EMA-was conducted. Participants were asked to complete four types of EMA surveys using a mobile app. For this analysis, only the number of completed random EMA surveys was used. Using linear mixed-effects modeling, we analyzed whether the number of completed random EMA surveys was associated with changes in self-reported dietary restraint, dietary disinhibition, and susceptibility to hunger measured using the Three-Factor Eating Questionnaire (TFEQ).

Results: During the 12-month study, 132 participants completed a mean of 1062 random EMA surveys (range: 673-1362). The median time it took for participants to complete random EMA surveys was 20 s and 90% of random EMA surveys were completed within 46 s. The number of completed random EMA surveys was not significantly associated with the TFEQ scores.

Conclusions: Intensive longitudinal EMA did not influence self-reported eating behaviors. The findings suggest that EMA can be used to frequently assess real-world eating behaviors with minimal concern about assessment reactivity. Nonetheless, care must be taken when designing EMA surveys-particularly when using self-reported outcome measures.

Level Of Evidence: Level III, prospective observational study.