Reliability and validity of the pathological gambling adaptation of the Yale-Brown Obsessive-Compulsive Scale (PG-YBOCS)

Abstract

The Yale Brown Obsessive Compulsive Scale adapted for Pathological Gambling (PG-YBOCS) was developed to measure the severity and change in severity of pathological gambling symptoms. The PG-YBOCS is a 10-item clinician-administered questionnaire that measures the severity of PG over a recent time interval (usually within the past one/two week(s)). In order to assess and validate the scale, it was administered to 337 subjects: 188 pathological gamblers and 149 healthy controls. Internal consistency and correlations between individual items and total score were assessed for various permutations of the sample. Other scales were administered to assess convergent, discriminant and content validity. Sensitivity to change was evaluated in treatment studies with fluovoxamine, lithium, and valproate. Each item was frequently endorsed across a range of severity. Good inter-rater reliability and internal consistency were obtained. The PG-YBOCS showed high validity and reliability for total score, item-total correlations, and for each subscale (Thoughts/Urges and Behavior). PG-YBOCS scores correlated with global severity and South Oaks Gambling Screen (SOGS) scores. The scale was also sensitive to change in pathological gambling severity. PG-YBOCS thus appears to be a reliable and valid measure of pathological gambling severity, and can be regarded as an important tool for clinicians and researchers treating pathological gamblers.