[Development of a scale to evaluate the rest levels of male workers]

Objectives　"Rest" has two aspects: "repose," to recover from physical or mental fatigue, and "restore," to re-establish physical, mental, and social health. Many male workers work for prolonged hours, and despite stress, they do not apply coping behaviors, unlike female workers. Consequently, taking sufficient rest is difficult for male workers. The aim of this study was to develop a scale incorporating multiple factors to evaluate the state in which male workers take rest.Methods　A questionnaire survey was conducted involving 330 male workers aged 20-59 years who had been engaged in two manufacturing industries. The questionnaire items were created with reference to an interview survey of male workers in the literature. After discussing with industrial hygiene experts and conducting a pretest to obtain surface validity, 70 items were used for analyses. In the exploratory factor analysis, promax rotation was used with the maximum likelihood method. In the confirmatory factor analysis, goodness of fit was confirmed with the covariance structure analysis. Health-related quality of life, job stress, work engagement, sleep, and self-assessment of rest were used to examine concurrent validity.Results　With the exploratory factor analysis, we introduced a scale containing 15 items, including three subscales: filling with spirit, enthusiasm for work, and recovery from fatigue. The reliability coefficient (Cronbach's alpha) of the three subscales and the overall scale ranged from 0.79 to 0.88 and 0.89, ensuring internal consistency. The confirmatory factor analysis showed a generally good fit. Their scores were correlated with many items of the health-related quality of life, job stress, work engagement, sleep, and self-assessment of rest.Conclusions　A 15-item "Rest Evaluation Scale" was created to evaluate the state in which male workers in the manufacturing industries take rest. Since the validity, reliability, and concurrent validity of this scale were satisfactory, this scale was considered to be an index evaluating the state of rest of male workers.