Published papers

Background: There have been few empirical studies to explain the individual differences in and the underlying mechanism behind the Job Demand-Control (DC) Model. Purpose: This study examined the lagged effects of active coping on stress responses (i.e., psychological distress and physical complaints) in the context of the DC Model using three-wave panel survey data with intervals of one month. Method: Participants were 193 employees working in a construction machinery company in Japan. Hierarchical multiple regression analyses were conducted to examine whether or not the effectiveness of active coping would be facilitated by job control as a coping resource. Results: The advantage of job control in combination with active coping became obvious after one month, which implies that job control has a delayed effect on coping effectiveness. However, the advantage disappeared after two months. These results suggest that the advantage of job control for active coping is limited in time. Conclusion: Conceptualization of job control as a coping resource seems to be useful in explaining how the DC Model influences employees' health, where time plays an important role. Copyright © Taylor & Francis Group, LLC.

© 2017 The distinctiveness between work engagement and burnout has long been an issue of debate. To address this issue, we use a recently developed technique by Yu et al. (2016) to specify and test a meta-analytic structural equation model (MASEM) which accounts for the non-independence between engagement and burnout as well as the simultaneous effects of all relationships in our model, based on job demands-resources (JD-R) theory. We also estimate the degree of variability of these relationships across subpopulations. We report the findings as a distribution of effect size estimates—each estimate in the distribution representing the true effect size for a potential subpopulation—around the mean average estimate for each relationship in the model. Based on the findings, we conclude that overall burnout and engagement display empirically distinct relationships within the JD-R model (i.e., they are not antipodal), particularly in terms of antecedents. Perhaps most interestingly, rather than a polar opposite pattern of relationships, challenge demands have a similarly positive relationship to both burnout (ß = 0.35, SD = 0.10) and engagement (ß = 0.35, SD = 0.08), suggesting that challenge demands simultaneously lead—in equal force—to both engagement and burnout. In addition, the distributions of effect sizes are nearly identical for both relationships, indicating that this holds true for nearly all subpopulations. As expected, hindrance demands have a positive relationship with burnout (ß = 0.31, SD = 0.10) and have a relatively weak, negative relationship on average to engagement (ß = −0.07, SD = 0.07); work resources have a negative relationship with burnout (ß = −0.15, SD = 0.06) and are positively related to engagement, but in absolute terms they are a stronger predictor of engagement (ß = 0.33, SD = 0.05). In terms of outcomes, burnout and engagement predict a variety of behavioral and attitudinal outcomes differentially from one another, although the differences are less clear due to wide variation in effect sizes in the population. Future research directions are discussed alongside practical implications.

Occupational conditions, together with socioeconomic status, may modulate sleep. This study examined the association of occupational conditions and socioeconomic status with actigraphic measures of sleep in workers. Fifty-five employees (40 ± 12 years) wore a wrist actigraph during sleep for seven consecutive nights. Sleep variables addressed included total sleep time, sleep efficiency, mean activity during sleep, sleep-onset latency, and wake after sleep onset. We also measured household income, occupational class, work schedule, weekly work hours, job demand, job control, worksite social support, effort-reward imbalance, organizational justice, and workplace social capital. Multiple linear regression models were used to determine the association of occupational indicators, socioeconomic status, as well as age and gender with each sleep variable. Higher workplace social capital was associated consistently with longer total sleep time (P < 0.001), higher sleep efficiency (P < 0.05) and lower mean activity during sleep (P < 0.07). Low occupational class (P < 0.01), higher job demand (P < 0.05) and lower job control (P < 0.05) were associated with longer total sleep time. No associations were significant for sleep-onset latency or wake after sleep onset. These preliminary results suggest that enhanced workplace social capital is closely associated with better quality and quantity of sleep. © 2014 European Sleep Research Society.

© 2014 Suzuki et al. Objectives: Sickness absence due to mental disease in the workplace has become a global public health problem. Previous studies report that sickness presenteeism is associated with sickness absence. We aimed to determine optimal cutoff scores for presenteeism in the screening of the future absences due to mental disease.Methods: A prospective study of 2195 Japanese employees from all areas of Japan was conducted. Presenteeism and depression were measured by the validated Japanese version of the World Health Organization Health and Work Performance Questionnaire (WHO-HPQ) and K6 scale, respectively. Absence due to mental disease across a 2-year follow-up was surveyed using medical certificates obtained for work absence. Socioeconomic status was measured via a self-administered questionnaire. Receiver operating curve (ROC) analysis was used to determine optimal cutoff scores for absolute and relative presenteeism in relation to the area under the curve (AUC), sensitivity, and specificity.Results: The AUC values for absolute and relative presenteeism were 0.708 (95% CI, 0.618-0.797) and 0.646 (95% CI, 0.546-0.746), respectively. Optimal cutoff scores of absolute and relative presenteeism were 40 and 0.8, respectively. With multivariate adjustment, cohort participants with our proposal cutoff scores for absolute and relative presenteeism were significantly more likely to be absent due to mental disease (OR= 4.85, 95% CI: 2.20-10.73 and OR= 5.37, 95% CI: 2.42-11.93, respectively). The inclusion or exclusion of depressive symptoms (K6≥13) at baseline in the multivariate adjustment did not influence the results.Conclusions: Our proposed optimal cutoff scores of absolute and relative presenteeism are 40 and 0.8, respectively. Participants who scored worse than the cutoff scores for presenteeism were significantly more likely to be absent in future because of mental disease. Our findings suggest that the utility of presenteeism in the screening of sickness absence due to mental disease would help prevent such an absence.

Purpose To investigate the cross-sectional association between organizational justice (i.e., procedural justice and interactional justice) and psychological distress or work engagement, as well as the mediating roles of other job stressors (i.e., job demands and job control, or their combination, effort-reward imbalance [ERI], and worksite support). Methods A total of 243 workers (185 males and 58 females) from a manufacturing factory in Japan were surveyed using a self-administered questionnaire including the Organizational Justice Questionnaire, Job Content Questionnaire, Effort-Reward Imbalance Questionnaire, K6 scale, Utrecht Work Engagement Scale, and other covariates. Multiple mediation analyses with the bootstrap technique were conducted. Results In the bivariate analysis, procedural justice and interactional justice were significantly and negatively associated with psychological distress; they were significantly and positively associated with work engagement. In the mediation analysis, reward at work (or ERI) significantly mediated between procedural justice or interactional justice and psychological distress; worksite support significantly mediated between procedural justice or interactional justice and work engagement. Conclusion The effects of organizational justice on psychological distress seem to be mediated by reward at work (or ERI) while those regarding work engagement may be mediated by worksite support to a large extent, at least in Japanese workers.

© 2017 The Author(s). The effects of Pokémon GO, a new mobile game application which utilizes augmented reality, on risky behavior and health have already been discussed in anecdotal evidence. However, there have been no studies about its effects on mental health. This study investigated the relationships between Pokémon GO and psychological distress from an existing workers' cohort in Japan. Online surveys were conducted to 3,915 full-time workers, at baseline (Nov 26, 2015-Feb 18, 2016) and at follow-up (Dec 1-4, 2016), using a self-report questionnaire. Pokémon GO players were defined as participants who had played Pokémon GO for one month or longer. Psychological distress was measured using validated scales. Of the completers, 246 (9.7%) had continued to play Pokémon GO. They were significantly younger than non-players. From the results of the general linear modeling, improvement in psychological distress was significantly greater among Pokémon GO players than among non-players (p = 0.025). Cohen's d for the difference in psychological distress was -0.20 (95% CI, -0.33, -0.07). Pokémon GO may be effective for improving psychological distress among workers. Although its effect size is small, the game could have positive effects on the mental health of the adult working population.

© 2016 National Institute of Occupational Safety and Health. This study examined whether a higher level of psychological detachment during non-work time is associated with better employee mental health (Hypothesis 1), and examined whether psychological detachment has a curvilinear relation (inverted U-shaped pattern) with work engagement (Hypothesis 2). A large cross-sectional Internet survey was conducted among registered monitors of an Internet survey company in Japan. The questionnaire included scales for psychological detachment, employee mental health, and work engagement as well as for job characteristics and demographic variables as potential confounders. The hypothesized model was tested with moderated structural equation modeling techniques among 2,234 respondents working in the tertiary industries with regular employment. Results showed that psychological detachment had curvilinear relations with mental health as well as with work engagement. Mental health improved when psychological detachment increased from a low to higher levels but did not benefit any further from extremely high levels of psychological detachment. Work engagement showed the highest level at an intermediate level of detachment (inverted U-shaped pattern). Although high psychological detachment may enhance employee mental health, moderate levels of psychological detachment are most beneficial for his or her work engagement.