Adaptation and Validation of the Swedish Five Factor Obsessive-Compulsive Inventory-Short Form in Adults With and Without Eating Disorder Psychopathology.

Background: Obsessive-compulsive personality disorder (OCPD) traits are highly prevalent in eating disorder populations and linked to greater symptom severity and poorer treatment outcomes, yet no validated dimensional measure of these traits exists for use in Swedish-speaking populations or in eating disorder contexts. The Five-Factor Obsessive-Compulsive Inventory-Short Form (FFOCI-SF) is a brief, dimensional instrument designed to assess OCPD-related traits within the five-factor model framework. This study aimed to adapt and validate the Swedish FFOCI-SF and to examine its psychometric functioning in adults with and without elevated eating disorder symptoms. Methods: Adults (n = 395) completed the FFOCI-SF, NEO-PI-3, DIP-Q, and EDE-Q. Psychometric properties were examined using a multimethod approach integrating structural equation modeling and classical test theory. Results: A revised 10-factor, 41-item model, reflecting the merger of three facets (C1-C3), demonstrated improved fit, clearer factor delineation, and acceptable-to-excellent internal consistencies (α = .66-.93). Convergent and discriminant validity were supported, and facet intercorrelations broadly aligned with theoretical expectations. Full measurement invariance was not supported; however, psychometric functioning was broadly comparable across the eating disorder group and the non-clinical comparison group. The eating disorder group showed systematically higher scores across most facets compared to the non-clinical comparison group. Conclusions: The revised Swedish FFOCI-SF exhibits a psychometrically sound and clinically meaningful 10-facet structure for use in both research and clinical settings. The findings further provide initial evidence for its applicability in eating disorder samples.