Reliability and Validity of the Korean Version of the Impaired Control Scale

Objective The aim of this study was to examine the reliability and validity of the Korean version of the Impaired Control Scale (K-ICS), a scale to screen patients with alcohol use disorder. Methods Participants were 173 inpatients with alcohol use disorder (AUD), and 174 normal controls (NC). Both AUD and NC groups completed the K-ICS as well as the Alcohol Dependence Scale (ADS), the Alcohol Abstinence Self-Efficacy Scale (AASES), the Brief Self-Control Scale (BSCS), and the Hospital Anxiety and Depression Scale (HAD). Results The internal consistencies of K-ICS were good in both AUD and NC. A good convergent validity was clearly shown by significant correlations with the ADS and the AASES, respectively. But the K-ICS had no or weak correlations with the BSCS and the HAD. The ROC curve analyses indicated that the optimal cut-off points of failed control (FC) and predicted control (PC) were estimated as >15 and >13, respectively. Hierarchical multiple regression analysis suggested that FC is a robust predictor of the severity of AUD. Conclusion The K-ICS, especially FC subscale of it appears to be a valid and reliable measure of impaired control among both clinical and non-clinical sample.