Omid Massah - Substance Abuse and Dependence Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
Hassan Rafiey - Social Welfare Management Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
Schwann Shariatirad - Substance Abuse and Dependence Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; Students Research Center of International Campus, Tehran University of Medical Sciences, Tehran, Iran.
Seyed Ramin Radfar - UCLA Integrated Substance Abuse Programs, University of California, Los Angeles, California, United States.
Elaheh Ahounbar - Substance Abuse and Dependence Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
Ali Farhoudian - Substance Abuse and Dependence Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran; Department of Psychiatry, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.

Objectives: The follow-up treatment or rehabilitation and monitoring of patients with drug abuse disorders require an efficient tool with a convenient and short-time implementation to measure psychological aspects of dependence. The Leeds Dependence Questionnaire (LDQ) has such features; thus, the present study aimed at evaluating the validity and reliability of its Persian version. Methods: The current validation study explored the data obtained from ۱۴۲ substance dependent patients selected from drug addiction treatment centers in Tehran City, Iran. The criterion-related validity of the Persian version of the LDQ was evaluated by measuring its correlation with the Substance Dependence Severity Scale (SDSS). The construct validity of the Persian version of the LDQ was evaluated using the General Health Questionnaire (GHQ). Moreover, the internal consistency and reliability of this scale were calculated by Cronbach’s alpha coefficient and test-retest reliability methods, respectively.  Results: The correlation coefficients between the LDQ and SDSS and GHQ were ۰.۷۷۳ and ۰.۷۸۰, respectively; the correlations were statistically significant (P<۰.۰۰۱). A Cronbach’s alpha coefficient of ۰.۸۰۹ was obtained by investigating the internal consistency of the tool. Test-retest reliability for a two-week interval was ۰.۹۶۳. Discussion: The criterion-related validity, construct validity, internal consistency, and test-retest reliability values of the Persian version of the LDQ are approvable; therefore, it can be applied as a valid and reliable tool on the Iranian population.

Leeds dependence questionnaire, Substance-related disorders, Iran