Psychometric Properties of Korean Version of Modified Leeds Sleep Evaluation Questionnaire (KMLSEQ)

Abstract

Purpose: The Leeds Sleep Evaluation Questionnaire (LSEQ) translated into Korean was modified to easily apply and reduce respondents' confusion and was evaluated for psychometric properties and discriminant ability. Methods: A total of 960 Korean adults aged 45 years and older participated in this cross-sectional survey. To test reliability, validity and discriminant ability, Cronbach's alpha, correlation analysis, confirmatory factor analysis, simple regression analysis and receiver operating characteristics (ROC) curve analysis were used. Results: Item-total correlations ranged between 62~.85 and Cronbach's alpha was .95. Area under ROC was .86 (95% CI: .83~.90) and the optimal cutoff score was identified as <TEX>${\leq}$</TEX> 66 (sensitivity, .77; specificity, .84; positive/negative predictive values, .49/.95). Using this cutoff score, the prevalence of insomnia in the study sample was 25.8% and tended to be more common in female and older groups. Conclusion: The data supported the psychometric properties of Korean Modified Leeds Sleep Evaluation Questionnaire (KMLSEQ) as an acceptable sleep measurement. In addition, KMLSEQ is likely to be a useful screening tool for insomnia.