Factor structure of the 19-item Comprehensive Psychopathological Rating Scale Self-rating Scale for Affective Syndromes in a Swedish nationwide clinical sample of eating disorder patients

ObjectiveAnxiety and depression symptoms are common in eating disorders. To study these, we need high-quality self-report questionnaires. The 19-item self-rated Comprehensive Psychopathological Rating Scale for Affective Syndromes (CPRS-S-A) is not validated in eating disorders. We tested its factor structure, invariance, and differences its latent dimensions. MethodPatients were registered by 45 treatment units in the Swedish nationwide Stepwise quality assurance database for specialised eating disorder care (n = 9,509). Patients self-reported their anxiety and depression symptoms on the CPRS-S-A. Analyses included exploratory and confirmatory factor analysis in a split samples and invariance difference testing in subscales across eating disorders. ResultsResults suggested a four-factor solution: Depression, Somatic & fear symptoms, Disinterest, and Worry. Multigroup confirmatory factor analysis indicated an invariant factor structure. We detected the following differences: Patients with anorexia nervosa binge-eating/purging subtype scored the highest and patients with unspecified feeding and eating disorders the lowest on all subscales. Patients with anorexia nervosa or purging disorder show more somatic & fear symptoms than individuals with either bulimia nervosa or binge-eating disorder. ConclusionOur four-factor solution of the CPRS-S-A is suitable for patients with eating disorders and may help to identify differences in anxiety and depression dimensions amongst eating disorders. Significant Outcomes Symptoms of anxiety and depression in eating disorder patients load on four dimensions: Depression, Somatic & fear symptoms, Disinterest, and Worry. Patients with anorexia nervosa binge-eating/purging subtype show the largest depression and anxiety symptom burden while patients with subsyndromal forms of eating disorders show the lowest. Instead of calculating total scores of anxiety and depression, a dimensional approach delivers more fine-grained association results. Limitations Our sample consisted of eating disorder patients only and there was no healthy control group or data from patients with other psychiatric disorders for comparison. The sample consisted predominantly of women which limits the ability to identify sex differences. The sample included Swedish treatment seeking patients of mostly white European ancestry limiting the generalisability of our findings.