[THE EMPIRICAL DISTINCTIVENESS OF WORK ENGAGEMENT AND WORKAHOLISM AMONG HOSPITAL NURSES IN JAPAN : THE EFFECT ON SLEEP QUALITY AND JOB PERFORMANCE].

The aim of the present study is to demonstrate the distinctiveness of work engagement and workaholism by examining their relationships with sleep quality and job performance.A total of 447 nurses from 3 hospitals in Japan were surveyed using a self-administrated questionnaire including Utrecht Work Engagement Scale (UWES), the Dutch Workaholism Scale (DUWAS), questions on sleep quality (7 items) regarding (1) difficulty initiating sleep, (2) difficulty maintaining sleep, (3) early morning awakening, (4) dozing off or napping in daytime, (5) excessive daytime sleepiness at work, (6) difficulty awakening in the morning, and (7) tiredness awakening in the morning, and the World Health Organization Health Work Performance Questionnaire.The Structural Equation Modeling showed that, work engagement was positively related to sleep quality and job performance whereas workaholism negatively to sleep quality and job performance.The findings suggest that work engagement and workaholism are conceptually distinctive and that the former is positively and the latter is negatively related to well-being (i.e., good sleep quality and job performance).