Associations Between Daily EMA of Emotional Exhaustion and Monthly Burnout Symptoms During Work Reintegration: Longitudinal Multilevel Study.

Background: Burnout is increasingly conceptualized as comprising both stable, slowly changing features and more dynamic, fluctuating features, with emotional exhaustion widely regarded as one of burnout's core components. Traditionally, burnout has been assessed using retrospective self-report questionnaires, such as the Burnout Assessment Tool (BAT), administered at sporadic intervals. In contrast, ecological momentary assessment (EMA) enables high-frequency assessment of daily experiences while reducing recall bias. However, it is not well understood how EMA-based measures fluctuate and develop longitudinally within individuals or how they relate to retrospective burnout measures. Objective: This paper examined the relationship between 30-day aggregates of daily EMA-assessed emotional exhaustion, specifically the within-person mean level and variability (SD), and monthly burnout symptoms measured with the BAT. Methods: Eighteen participants undergoing work reintegration after stress- or burnout-related sick leave completed daily EMAs of emotional exhaustion (N=3157) and monthly BAT questionnaires over 6 months (N=94). For each monthly BAT assessment, EMA data from the preceding 30 days were aggregated into within-person mean and SD values. Linear mixed-effects models with random intercepts and time effects were fitted separately for each BAT subscale. Additionally, intraclass correlation coefficients (ICCs) were calculated to quantify the proportion of variance attributable to between-person differences. Results: ICCs indicated that a large proportion of variance in the BAT subscales was attributable to between-person differences, whereas daily EMA emotional exhaustion showed relatively greater within-person variability. Significant time-related changes were observed for the BAT subscales of Cognitive Impairment, Mental Distance, and Emotional Impairment. Within-person increases in the EMA mean of emotional exhaustion were significantly associated with higher scores on BAT Exhaustion ( Conclusions: EMA-based aggregates showed partial correspondence with monthly burnout scores. Within-person increases in mean daily emotional exhaustion were associated with higher subsequent scores on the BAT Exhaustion and Cognitive Impairment subscales, but EMA-based variability was not associated with any BAT subscale. Together with the ICC results, these findings suggest that EMA-based aggregates of emotional exhaustion can reflect short-term fluctuations and longer-term changes in symptom severity of exhaustion and cognitive impairment. Retrospective questionnaires remain useful for global symptom assessment or diagnoses at specific time points but appear less well suited for tracking within-person changes and supporting personalization. These results highlight the importance of aligning the choice of assessment with temporal and clinical goals.