Ecological momentary assessment of affect, stress, and binge-purge behaviors: Day of week and time of day effects in the natural environment

Objective: The present study examined ecological momentary assessments of binge/vomit behavior, mood, and type and severity of stressors in a sample of 133 women with bulimia nervosa. Method: Participants completed an ecological momentary assessment protocol for a period of 2 weeks. Results: Mixed-effects and multilevel logistic models revealed significant variation across time of day and day of the week in the occurrence of binging, vomiting, positive and negative affect, and the severity and types of stressful events. Discussion: These findings explicate how momentary and daily experiences vary in the natural environments of women with bulimia nervosa, and document critical time periods for intervention.