The Padua Inventory–Washington State University Revision of Obsessions and Compulsions: A Reliability Generalization Meta-Analysis

Abstract

The Padua Inventory–Washington State University Revision (PI–WSUR) is a frequently used test to assess obsessive–compulsive symptoms in screening and clinical contexts. A reliability generalization meta-analysis was carried out to estimate the average reliability of the PI–WSUR scores and its subscales and to search for characteristics of the studies that can explain the heterogeneity among reliability coefficients. A total of 124 independent samples reported some coefficient alpha or test–retest correlation with the data at hand for the PI–WSUR scores. The average internal consistency reliability of the PI–WSUR total scores was .929 (95% CI [.922, .936]), and for the subscales, the means ranged from .792 to .900. The test–retest reliability for PI–WSUR total scores was .767 (95% CI [.700, .820]), with the subscales ranging from .540 to .790. Moderator analyses revealed a positive relationship between the standard deviation of PI–WSUR total scores and alpha coefficients, as well as higher reliability estimates for the original version of the test and for studies from North America. The reliability induction rate for the PI–WSUR was 53.7%. Regarding reliability, the PI–WSUR ranks among the best scales for assessing obsessive–compulsive symptoms. Internal consistency reliability was excellent for the PI–WSUR total score and good for the subscales.