The Assessment of Obsessive-Compulsive Symptoms

Abstract

Objective: We examined the reliability and validity of the 60-and 41-item versions of the Padua Inventory (PI and PI-R) which were developed to assess the frequency and severity of obsessive-compulsive symptoms, in a Turkish population. Method: The sample consisted of 43 OCD patients, 30 non-OCD patients with other anxiety disorders, 30 nonobsessional depressed patients, 76 healthy adults, and 181 undergraduate students. We investigated internal consistency, test-retest reliability, and factor structure, concurrent and discriminant validity. Results: Psychometric analyses showed that both the original PI and PI-R had a high internal consistency and test-retest reliability. While principal factor analysis of the 41 items revealed six factors that are consistent with the PI-R, the factor structure of the original scale was not confirmed. All the subcales and total scores for both instruments were significantly correlated with the Yale-Brown scores except for the impulses subscale. There were significant differences between OCD patients and nonclinical samples in all total and subscale scores for both instruments. OCD patients scored significantly higher on the total, contamination/washing and checking subscales for both instruments than nonobsessional anxious, and depressed patients. While OCD patients scored significantly higher on the PI-R rumination scale than nonobsessional anxious patients, their PI impaired control subscale score was not different from that of the other clinical groups. Conclusions: The Turkish version of the PI has appropriate reliability and validity for assessing the frequency and severity of obsessive-compulsive symptoms.