Psychometric evaluation of the Chinese Version of the Stimulant Relapse Risk Scale (C-SRRS) in Patients with Methamphetamine Use Disorder

Background: Evaluating the risk of relapse is a pivotal step in the treatment of individuals with methamphetamine use disorder (MUD). The 30-item Stimulant Relapse Risk Scale (SRRS) was originally developed in Japan to meet the demand. This study examined the reliability, validity, and factor structure of the Chinese version of the SRRS (C-SRRS) for patients with MUD. Methods 247 patients with MUD self-rated the C-SRRS. Cronbach’s alpha coefficients and inter-item correlation analysis were used to assess the internal consistency reliability. Construct validity was determined through confirmatory factor analysis (CFA), and concurrent validity was examined using the visual analogue scale (VAS) for drug craving and the severity of dependence scale (SDS). We followed the participants for 1 year and assessed the predictive validity based on the correlation of C-SRRS scores with the relapse rate within 3, 6, and 12 months of follow-up. Results CFA revealed satisfactory model fit estimates for 22 items of CRRS that consisted of four subscales. The four-factored 22-item C-SRRS had adequate internal consistency with Cronbach’s alphas ranging from 0.76 to 0.92. The 22-item C-SRRS scores were significantly correlated with the VAS and SDS scores as well as the relapse rate within 3, 6, and 12 months, indicating good concurrent and predictive validity of this scale. The receiver operating characteristic curve revealed a cutoff score of 40 could discriminate between high and low severity of methamphetamine dependence (area under the curve = 0.71, p < 0.01). Conclusions The 22-item C-SRRS that consists of four subscales is a valid and reliable instrument to assess the relapse risk in patients with MUD.