Psychometric properties of the Padua Inventory in a sample of Japanese university students

The psychometric properties and factor structure of the Padua Inventory (PI), a measure of obsessive–compulsive phenomena, were examined in a non-clinical sample of 671 Japanese university students. Results showed high internal consistencies of both the total scale and its subscales in the Japanese sample. A factor analysis replicated a four-factor structure, consisting of three factors corresponding to those found in previous studies (‘Impaired control of mental activity’, ‘Being contaminated’ and ‘Checking behaviour’) and one factor (‘Impulsive thoughts’), which partly differed from that found previously. The total score of the PI correlated moderately with two Obsessive–Compulsive Personality Disorder (OCPD) measures, but two subscales of the PI did not show a correlation with OCPD. Results of a multiple regression analysis revealed the PI did not explain the degree of OCPD traits well, suggesting the PI measures OCD traits better than OCPD in non-clinical samples.