Objective: The psychometric properties and factor structure of the Persian Padua Inventory Washington State University Revision (PI-WSUR), a measure of obsessive- compulsive phenomena, was examined in a non-clinical sample of 348 Iranian university students.
Method: The PI-WSUR was translated into Persian, and its back translation was controlled by the author inventory. A pilot study based on cultural differences was carried out on twenty students. The study subjects consisted of 348 university students, and they completed PPI, OCI-R, MOCI, BAI, STAI, BDI-II and the demographic inventory.
Results: The factor analysis of the PI-WSUR, exhibited eight factors similar but not identical with factor structure in previous studies. as the eight factors are as follows: contamination obsessions; washing compulsions; ordering compulsions; checking compulsions; obsessional thoughts to harm self/others; obsessional thoughts about violence; obsessional impulses to harm self/others; and obsessional impulses to steal. The result also indicated excellent internal consistency (Cronbach alpha= 0.92), Spearman split test (0.95) and test- retest (r= 0.77). We assessed the concurrent validity of the PPI in relation to the Obsessive Compulsive Inventory-Revised (OCI-R), and the Maudsley Obsessive- Compulsive Inventory (MOCI).
Conclusion:The Iranian version of the PI to some extend remains the sound psychometric properties of the original version.