Validation of the Chinese version of the Opiate Addiction Severity Inventory (OASI) and the Severity of Dependence Scale (SDS) in non-institutionalized heroin users in China.

No fully validated Chinese instrument measuring severity of drug dependence exists. The Chinese Opiate Addiction Severity Inventory (OASI) and the translated Chinese version of the Severity of Dependence Scale (SDS) were validated in this study. A total of 178 eligible participants were recruited using snowballing method. The 11-item revised version of OASI (OASI-R) exhibited good reliability (item-total correlation coefficients ranged from 0.50 to 0.73, Cronbach's alpha was 0.85, test-retest Intra-class Correlation Coefficient was 0.81, p < 0.001). Two factors were identified by principal component method and correlated significantly with the Quality of Life-Drug Addiction (QOL-DA). The 3-item revised version of SDS (SDS-R) was one of the two factors of SDS (item-total correlation coefficients were 0.79 to 0.86, Cronbach's alpha was 0.78, test-retest Intra-class Correlation Coefficient was 0.64, p < 0.001). It correlated significantly with QOL-DA. OASI-R and SDS-R were also significantly correlated with each other and with some heroin-related characteristics. The validation of the Chinese version of OASI-R and SDS-R would facilitate research in different Chinese populations. SDS has been translated to different languages and the Chinese version allows for international comparison.