Psychometric Properties of 20-Item and 10-Item Persian Versions of Drug Abuse Screening Test

Introduction: Substance use disorder is one of the most critical social problems in Iran. For this disorder, weneed a proper assessment tool based on our indigenous culture. Objective: This study assesses the factor structure and psychometric properties of 10-item and 20-item Persian versions of Drug Abuse Screening Tests (DAST-10 and DAST-20). Materials and Methods: In this cross-sectional study, we randomly selected 200 participants referred to addiction treatment centers in Rasht City, Iran. After translation to Persian and back-translation to English, the face and content validity of DAST-10 and DAST-20 Persian versions were evaluated using the opinions of a panel of expertsand calculatingthe content validity ratio and content validity index. Then, the construct validity was evaluated by Confirmatory Factor Analysis(CFA), the Cronbach α coefficient was used for assessing internal consistency, and the Intraclass Correlation Coefficient (ICC) was used for assessing test-retest reliability. Results: The Mean±SD age of participants was 39.02±11.67 years. The majority (50%) were in the age range of 30-50 years. Based on the CFA fit indices, the two instruments had a good fit to the data, confirming the theoretical model Root Mean Square Error of Approximation (RMSEA) (RMSEA for DAST-20=0.080; RMSEA for DAST-10=0.055). The Cronbach α values ​​of DAST-20 and DAST-10 were 0.772 and 0.749, respectively, indicating their good and acceptable internal consistency. Their test-retest reliability was reported at 0.997 and 0.995 based on the results of ICC, respectively. There was a strong and significant positive correlation between the scores of Persian DAST-20 and DAST-10 (r=0.851, P=0.001). Conclusion: The DAST-20 and DAST-10 Persian versions which after correcting the model using confirmatory factor analysis, they were studies in DAST-8 and DAST-16 have good validity and reliability and can be used for screening the possible involvement of drugs in Iranian samples.