Psychometric Properties of the Polish version of the Drug-Use Disorders Identification Test

Background: Substance use is a growing problem worldwide, and there is a great need to develop national policies addressing prevention and treatment of substance-use disorders (SUD). However, the lack of a commonly used, valuable diagnostic tool to assess the symptoms of SUDs precludes comparison of the prevalence of drug-use problems as well as the efficacy of policy strategies applied in different countries. This study was conducted to validate one of the commonly used scales the Drug Use Disorders Identification Test (the DUDIT) for use in Polish condition. Objectives: The aims of this study were to test the reliability of the DUDIT in the Polish population, to confirm the comparative stability of the factor structure of the instrument, and to verify previously proposed DUDIT cutoff scoring. Methods: The group of drug users comprised 127 patients aged 19-40 years (mean age 30.37, SD 6.36) with a diagnosis of SUD, while the control group consisted of 533 students aged 19-25 years (mean age 20.72, SD 1.88). All participants completed the Polish version of the DUDIT. Internal consistency of the Polish version of the DUDIT was determined, and subsequently external validation was performed. Results: Analysis showed that the Polish version of the DUDIT was characterized by a good reliability based on Cronbach's alpha, with a value of 0.92. The between-group comparison revealed a significant difference between the control group and substance-dependent patients corresponding to a large effect size (Cohen's d = 3.27). The receiver-operating characteristic analysis, comparing the DUDIT score to the ICD-10 diagnosis of SUD, showed an optimal cutoff value of 7 points, with a sensitivity of 0.929 and a specificity of 0.974. Conclusion: These results constitute preliminary evidence that the Polish version of the DUDIT may be a valid and reliable screening tool for drug-use disorders in the Polish population.