No abstract

BACKGROUND Many of the existing scales for microstressor assessment do not differentiate between objective (i. e., observable) stressor events as opposed to stressful cognitions or concerns and often mix these items with other aspects of stress, such as perceived stressor severity, the evoked stress reaction or further consequences on health. This may result in spurious associations with other questionnaires measuring such constructs. Since most scales were de-veloped several decades ago, modern life stressors may not be represented. OBJECTIVE To develop a questionnaire that a) focuses on the retrospective assessment of objective microstressors over a one-week period and b) separates stressor occurrence from perceived stressor severity. METHODS Cross-sectional (N=109) and longitudinal studies (N=10 and N=70) were conduct-ed. In the longitudinal studies, Ecological Momentary Assessment (EMA) was used to com-pare stressor data, collected five times per day for 30 days, with retrospective reports (end-of-day, -week). Pearson correlations and multilevel-modelling were used in the analyses. RESULTS High correlations were found between the end-of-week, end-of-day and EMA data for microstressor occurrence (counts) (r ≥ .69 for comparisons per week, r ≥ .83 for cumulated data) and for mean perceived microstressor severity (r ≥ .74 for comparisons per week, r ≥ .85 for cumulated data). The end-of-week questionnaire predicted the EMA assessments suf-ficiently (counts: b= .03, 95% CI= .02 to .03, P<.001; severity: b= .67, 95% CI= .52 to .82, P<.001), the association did not change significantly over the period of four subsequent weeks. CONCLUSIONS Our results provide evidence for the ecological validity of the MIMIS questionnaire. CLINICALTRIAL none