LAUSR

Abstract Background The Florida Obsessive-Compulsive Inventory (FOCI) is a self-report measure designed to assess obsessive-compulsive symptom presence and severity. This study evaluated the reliability and validity of the Chinese version of the FOCI and its optimal cut-off score. Methods A systematic translation process was used to translate the English FOCI into Chinese. Four hundred and fifty-three adults participated in the study including 153 individuals with OCD, 150 case-controls with a primary anxiety or depressive disorder, and 150 healthy controls. All three groups were evaluated by a set of measures including the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), the FOCI, the Obsessive-Compulsive Inventory-Revised (OCI-R), the Beck Depression Inventory-Second Edition (BDI-Ⅱ), the Beck Anxiety Inventory (BAI), and the Short Form Health Survey (SF-36). Among the OCD patients, a subset of 47 participants were evaluated over a two-week interval to assess test-retest reliability of the FOCI. Results The internal consistency of the FOCI Symptom Checklist and Severity Scale in the OCD group were0.813 and 0.840. Two-week test-retest reliability were 0.934 and 0.935. Convergent validity of the FOCI Symptom Checklist and Severity Scale were both strong. Correlations with diverging constructs were modest overall. Factor analysis of the FOCI Severity Scale was conducted, identifying a single factor solution explaining 62.3% of the variance. FOCI scores among those in the OCD group were higher than those from the case-control and healthy control groups. A cut-off score of 8 was optimal in predicting caseness. Conclusions The Chinese version of the FOCI demonstrated good psychometric properties including internal consistency, test-retest reliability, a stable factor structure, and convergent and divergent validity. A cut-off score of 8 was optimal in predicting caseness.