Gambling disorder (GD) and substance use disorder (SUD) have mutual impact and each couldaggravate the effects of the other. This is the first study on GD among Iranian substance users to develop andvalidate a GD Screening Questionnaire-Persian (GDSQ-P).
Iranian male adults (n = 503) with SUDs were recruited via clustered sampling. Problem gamblingscreening instruments and Diagnostic and Statistical Manual of Mental Disorders-5th Edition (DSM-5)criteria for GD were used to develop the tool which was sequentially assessed for face validity, contentvalidity index (CVI), content validity ratio (CVR), and reliability (Kuder-Richardson coefficient). To establishconstruct validity, interviews based on DSM-5 as a gold standard method were used. A receiver operatingcharacteristic (ROC) curve was conducted to determine sensitivity and specificity.
After removing items with low CVI values, 27 final items remained in GDSQ-P with impact scoregreater than 1.5. Card games (33.8%), dice gambling methods (26.6%), betting on sports teams and players(24.1%), and betting on horseback, rooster, pigeon, dog, or other animals (16.7%) were common gamblingmethods among participants. Overall Kuder-Richardson coefficient was 0.95. Cut-off threshold for GDSQ-Pwas calculated as 4.5 with 98.9% sensitivity and 98.3% specificity. The interviewers confirmed GD forparticipants based on DSM-5 as the gold standard. The prevalence of GD among participants was 17.9%based on GDSQ-P and 19.1% based on DSM-5 criteria.
GDSQ-P is a valid and reliable tool to screen for GD in SUD treatment centers and probably inthe general population.