Validity and Reliability of the Thai Version of the Questionnaire for Measuring the Severity of Alcohol Dependence among General Population

Abstract

The objective of this study was to test the validity and reliability of a questionnaire developed to measure the severity of alcohol dependency in community samples of drinkers (SADQ-C). It was conducted in three phases: phase 1 was the translation, blind back-translation and the scale confirmation; phase 2 - determination of clarity and readability of the scale; and phase 3 - evaluation of psychometric properties of the scale which was reviewed for content validity, and field tested with 332 people randomly recruited from 3 districts in Chiang Mai Province. It was found that the values of content validity index of item-level and the overall score level were 1.00 and 1.00, respectively. The psychometric property of the questionnaire was evaluated by people in community, and the findings indicated that there were 20 items which were correlated with the overall score (r ≥ 0.4). These 20 items had good power to discriminate mild and severe alcohol dependence (p<0.01). Exploratory factor analysis revealed that the percentage of variance for the questionnaire was 71.74; and the reliability coefficient alpha was 0.96. The authors concluded that the alcohol dependence severity questionnaire has high validity and high reliability; and could be used as a tool to assess the severity of alcohol dependence among people in community.