Background: The Beck Depression Inventory II (BDI-II) has been accepted as one of the most commonly used self-report measures for depression. However, there is no study examining the psychometric properties of the BDI-II among substance users in low- and middle-income countries such as Myanmar. Therefore, this study aimed to evaluate the suitability of using this instrument in substance users and to examine the reliability and diagnostic efficiency to be compared with the International Classification of Diseases (ICD-10) among substance users in Northern Shan State of Myanmar.
Methods: A respondent-driven sampling (RDS) method was applied for recruiting the participants in this study, and total 230 substance users were recruited. On the other hand, 50 participants who visited the drop-in center (DIC) were screened for depressive symptoms using ICD-10 during the days when one consultant psychiatrist doctor was presented. These participants were interviewed face-to-face by the consultant psychiatrist using a semi-structured questionnaire including the Myanmar version of the BDI-II (mBDI-II).
Results: The mBDI-II showed moderate accuracy with an area under the curve of 0.68. The optimal cutoff score was 10 with the highest Youden index (0.48), and it had high sensitivity and specificity (0.78 and 0.70). The Cronbach's alpha coefficients for clinically depressed and non-clinically depressed substance users were 0.91 and 0.93, respectively. Confirmatory factor analysis of the mBDI-II indicated that a three-factor solution (cognitive, affective, and somatic) was the best fit for substance users.
Conclusions: The mBDI-II has sound psychometric properties among substance users with moderate accuracy and range of possible cutoff scores together with sensitivity and specificity.
Keywords: Beck Depression Inventory; Depression; Diagnosis efficiency; International Classification of Diseases; Reliability; Substance users.