Validation of the International Adjustment Disorder Questionnaire and Adjustment Disorder in Türkiye

This study examined the psychometric properties of the International Adjustment Disorder Questionnaire and investigated the prevalence and correlates of adjustment disorder in a large community sample recruited via online snowball sampling in Türkiye (N = 1153; Mean age = 28.55, SD = 10.02). Participants completed self-report measures assessing adjustment disorder, depression, and anxiety symptoms based on ICD-11 criteria. Confirmatory factor analysis supported a correlated two-factor structure (preoccupation and failure to adapt) demonstrating good model fit. Convergent validity was evidenced by positive correlations between adjustment disorder symptoms and both depression and anxiety. The prevalence of probable adjustment disorder in the sample was 14.1%. Adjustment disorder scores were significantly associated with gender in bivariate analyses; however, after psychosocial stressors were included, the gender effect lost significance. Financial problems emerged as the most frequently reported psychosocial stressor. In regression analyses, all psychosocial factors, except “my own health problems,” significantly predicted symptom severity of the adjustment disorder. The findings support the two-factor model of adjustment disorder proposed in the ICD-11 and highlight the importance of demographic and contextual stressors in its development. Based on a stress-response framework, the results suggest that perseverative, stressor-anchored cognition and impaired functional re-engagement are distinct yet related processes in adjustment disorder.