Reliability and validity of the Japanese version of the Overwork Climate Scale.

This study aimed to investigate the validity and reliability of the Japanese version of the Overwork Climate Scale. Japanese workers were invited to participate in online surveys at baseline and 1-month follow-up. The Overwork Climate Scale was translated into Japanese, according to international guidelines. Reliability was assessed using Cronbach's alpha and the intra-class correlation coefficient (ICC), while structural validity was evaluated through confirmatory factor analysis (CFA). Psychological job demands, work engagement, psychological safety, and workaholism were assessed for convergent validity. The number of respondents was 302 at baseline and 169 at follow-up. Results indicated robust Cronbach's alpha values of 0.86 (for overwork endorsement) and 0.80 (for lacking overwork reward) at baseline, complemented by ICC of 0.89 and 0.82, respectively. CFA confirmed the suitability of the two-factor model. Moreover, the Japanese Overwork Climate Scale exhibited significant correlations with anticipated constructs. Structural equation modeling revealed a consistent association between overwork climate and both workaholism and work engagement, similar to the original version. In conclusion, the Japanese version of the Overwork Climate Scale demonstrates acceptable levels of reliability and validity, warranting its potential adoption among Japanese workers.

Characteristics of long working hours and subsequent psychological and physical responses: JNIOSH cohort study.

OBJECTIVES: This study aimed to examine the prospective association among objectively measured average working hours (AWHs), frequency of long working hours (FLWHs; defined as ≥205 working hours/month (≥45 hours/week)) for 6 months, and workers' self-reported psychological and physical health. METHODS: The study included 15 143 workers from 5 Japanese companies. We collected monthly attendance records over 6 months before distributing a questionnaire survey on psychological/physical stress responses and work-related demographics. We then evaluated the associations of those attendance records with psychological/physical measures using analysis of covariance adjusted for sex, age, employment, job type, working conditions, work site and experience of emergency state due to COVID-19. RESULTS: Irritability, anxiety and depression were significantly greater at ≥180 hours (≥45 hours/week), and fatigue and lack of vigour were greater at ≥205 hours than those of the normal working-hour group (140-180 hours/month [35-45 hours/week]). Psychological indices increased significantly with FLWH, with ≥3 times for irritability, depression and fatigue; ≥2 times for lack of vigour; and ≥1 time for anxiety when compared with no long working hours. No significant associations were observed between AWH or FLWH and physical stress responses. CONCLUSIONS: Longer AWH was associated with higher levels of psychological stress responses. The effects of FLWH in the past 6 months varied among the psychological stress responses and did not occur for physical complaints. Under circumstances requiring long hours, workers' mental health should be protected through minimising the frequency of long work hours.

Health problems associated with single, multiple, and the frequency of months of objectively measured long working hours: a cohort study by the National Institute of Occupational Safety and Health, Japan.

PURPOSE: We aimed to examine the prospective associations of monthly working hours measured in a month, the 6-month averaged hours, and the frequency of long working hours (≥ 205 h/month) during the past 6 months with health indicators. METHODS: This study included 6,806 Japanese company workers (response rate = 86.6%). Data on the workers' monthly attendance during the second half of fiscal year 2016 and annual health checkups in fiscal years 2016 and 2017 were collected. We evaluated the association of the above three types of monthly working hours with subsequent health checkup data in fiscal year 2017. We adjusted for the corresponding data in fiscal year 2016. RESULTS: Multivariate logistic regression analyses revealed significant associations between monthly working hours and workers' systolic and diastolic blood pressure as well as aspartate aminotransferase, alanine aminotransferase, low-density lipoprotein cholesterol (LDL), and triglyceride levels. However, the associations were not consistent between months. The average monthly working hours were significantly associated with higher LDL levels for the 220-240 h/mo group (OR: 1.49, 95%CI: 1.07-2.08) and lower triglyceride levels for the < 140 h/mo group (OR: 0.15, 95%CI: 0.03-0.77), compared to the 140-180 h/mo group. The frequency of long working hours was significantly associated with higher LDL levels. CONCLUSIONS: Working hours over several months produced various associations with health indicators compared to those measured in a single month. Our present data suggest that the effects of average or frequency of long working hours during the past 6 months are likely to appear in LDL levels.

Study profile: protocol outline and study perspectives of the cohort by the National Institute of Occupational Safety and Health, Japan (JNIOSH cohort).

How work burden affects physical and mental health has already been studied extensively; however, many issues have remained unexamined. In 2017, we commenced a prospective cohort study of workers at companies in Japan, with a follow-up period of 5-10 years, in order to investigate the current situation of overwork-related health outcomes. From 2017 to 2020, a target population of 150,000 workers across 8 companies was identified. Of these, almost 40,000 workers agreed to participate in the baseline survey. Data on working hours, medical check-up measurements, occupational stress levels, and lifestyle habits were collected. The average age of the participants at baseline was 39.2 ± 11.7 years; 73.1% were men, and 87.7% were regular employees. The most common working hours by self-reported was 41-50 hours per week during normal season, and it increased to more than 50 hours during busy season. Furthermore, more than half of the participants reportedly experienced a form of sleep problem, and the percentage of those who experienced nonrestorative sleep was particularly high.

Reliability and validity of the Japanese version of the psychological safety scale for workers.

Although an increasing number of studies on psychological safety at workplaces has been conducted in both western and eastern countries, there are few empirically validated measures in Japan. Our purpose was to investigate the validity and reliability of the Japanese version of the Psychological Safety Scale. Japanese workers were invited to participate in online surveys at baseline and at one-month follow-up (N=320). The Psychological Safety Scale was translated into Japanese according to international guidelines. Social support at workplace, work engagement, organization-based self-esteem, organizational justice, and job satisfaction were measured. Cronbach's alphas and intra-class correlation coefficient (ICC) were examined for reliability, and its validity was tested by confirmatory factor analysis and correlational analyses. The results of the survey showed that respondents were 287 at baseline and 236 at follow-up. Cronbach's alphas of the Psychological Safety Scale were 0.91 (baseline) and 0.88 (follow-up), and ICC was 0.87. Confirmatory factor analysis demonstrated a marginally acceptable fit. Overall, the Japanese Psychological Safety Scale had moderate to strong correlations with other scales. In conclusion, the Japanese version of the Psychological Safety Scale had acceptable levels of reliability and validity, and may be applicable for use in Japanese workers.

Objective and Subjective Working Hours and Their Roles on Workers' Health among Japanese Employees.

Table 3 of the above paper appeared incorrectly in print. Percentage figures on the table were inadvertently listed as negative values. These errors were corrected in online versions of this paper, as shown below.

Objective and subjective working hours and their roles on workers' health among Japanese employees.

This study investigated the correlation between objective and subjective working hours (OWH and SWH, respectively) and their relation to the workers' health. The study included 6,806 workers of a Japanese company (response rate=86.6%). OWH were collected as the monthly data during fiscal year 2017 from the company record. SWH were self-reported as the weekly data during the past month in November 2017. Both OWH and SWH corresponded to the same period of one month (October 2017). Additionally, the data for the annual health checkup in fiscal year 2017 and self-reported mental health in November 2017 were collected. The results indicated that the longer OWH was related to more underestimation of SWH. The analyses of covariance adjusted for the selected variables showed that irrespective of OWH or SWH, significant relationships were found for stress responses but not for body mass index, aspartate and alanine aminotransferase, fasting blood glucose, hemoglobin A1c, high-density lipoprotein cholesterol, or triglyceride. However, significant relationships with only OWH were noted for systolic and diastolic blood pressure, low-density lipoprotein cholesterol, gamma-glutamyl transpeptidase, and positive work-related state of mind. The present findings show that SWH should be used carefully when assessing the health effects of long working hours.

Choroidal folds in acute-stage vogt-koyanagi-harada disease patients with relatively short axial length.

PURPOSE: To report 2 cases of Vogt-Koyanagi-Harada disease accompanied by remarkable choroidal folds in the acute stage. The early indicator of recurrence in these 2 cases was the identification of choroidal folds by spectral-domain optical coherence tomography (SD-OCT). CASE REPORTS: A 68-year-old woman (Case 1) presented with visual loss in both eyes. Funduscopic examination revealed optic disc swelling and serous retinal detachment in both eyes. SD-OCT revealed remarkable choroidal folds and serous retinal detachment. After the initiation of systemic steroid treatment, choroidal folds disappeared rapidly and the amount of serous retinal detachment reduced remarkably. Choroidal folds observed on SD-OCT were the early indicators of recurrence prior to the emergence of serous retinal detachment. A 62-year-old woman (Case 2) presented with bilateral blurred vision and metamorphopsia. SD-OCT showed remarkable choroidal folds and serous retinal detachment in both eyes. After the initiation of systemic steroid treatment, choroidal folds and serous retinal detachment disappeared. At the time of recurrence, choroidal folds were observed by OCT. DISCUSSION: During monitoring of Vogt-Koyanagi-Harada disease treatment, choroidal folds could be an early sign of recurrence. When choroidal folds are observed and recognized as an early indicator of recurrence, a prompt increase in steroids can improve the patients' prognosis. Finally, both cases presented here had relatively short axial lengths, and we speculate that a shortened axial length may be a cause of choroidal folds in the acute stage of the disease.

Higher concentration of transforming growth factor-beta in aqueous humor of glaucomatous eyes and diabetic eyes.

PURPOSE: Diabetic retinopathy and glaucoma are the primary causes of acquired blindness. Cytokines including transforming growth factor (TGF)-beta may be involved in these diseases. We therefore collected aqueous humor samples from patients with glaucoma and/or diabetes who were undergoing surgery, and determined the concentration of TGF-beta. METHODS: Aqueous humor samples were collected from 80 patients (84 eyes), including 19 eyes with primary open-angle glaucoma (POAG), 22 eyes with diabetes, and 18 eyes with diabetes complicated with POAG. Twenty-five eyes with cataract served as controls. The concentration of TGF-beta1 or TGF-beta2 was measured by enzyme-linked immunosorbent assay. RESULTS: The concentration of TGF-beta1 was less than 0.1 pg/mL in all of the groups. In contrast to controls who had 1001.4 +/- 444.1 pg/mL, the concentration of total TGF-beta2 in the diabetes group was 1715.6 +/- 882.1 pg/mL, and that in the diabetes complicated with POAG group was 1692.9 +/- 361.9 pg/mL. These were significantly higher than that in controls. In contrast to the controls who had 321.2 +/- 197.9 pg/mL, the concentration of mature TGF-beta2 with POAG was 822.5 +/- 484.4 pg/mL, and that of diabetes complicated with POAG was 1058.9 +/- 648.4 pg/mL. These were significantly higher than that in the controls. The eyes with diabetes complicated with POAG also had a significantly higher concentration than the eyes with diabetes alone. CONCLUSION: Total TGF-beta2 and mature TGF-beta2 in high concentration may correlate with progression of POAG, diabetes, and diabetes complicated with POAG.