Relationships between sleep efficiency and lifestyle evaluated by objective sleep assessment: SLeep Epidemiology Project at University of Tsukuba.

Objectively measured sleep efficiency has recently been shown to be associated with health problems. Although several factors have previously been reported to be associated with sleep efficiency, most of these studies were conducted on older or younger adults, and the factors associated with sleep efficiency in healthy workers remain unknown. The aim of this study was to investigate the relationship between sleep efficiency and lifestyle factors using sleep measurement data recorded by an activity meter worn by workers. In total, 693 workers (male, 43.6%; mean age, 42.7 ± 11.3 years) were recruited from five offices in 2017. Sleep was measured over the period of 1 week by actigraphy. Workers' attributes, lifestyle habits, and occupational stress were identified using a questionnaire, and the association of sleep efficiency with lifestyle, occupational stress, and attributes was explored by logistic regression analysis. A logistic regression analysis using attributes and occupational stress as adjustment variables revealed that "longer sleeping hours on weekends than on weekdays" [odds ratios (OR), 0.66; 95% confidence interval (CI), 0.47-0.94], "water ingestion at bedtime" [OR, 2.09; 95% CI, 1.28-3.41], and "smartphone use at bedtime" [OR, 1.90; 95% CI, 1.28-2.83] were associated with decreased sleep efficiency. This study found that lifestyle habits were associated with sleep efficiency among workers. It is necessary to verify whether intervention in these lifestyle habits would contribute to the improvement of sleep efficiency in future studies.

Prevalence, characteristics, and psychological outcomes of workplace cyberbullying during the COVID-19 pandemic in Japan: a cross-sectional online survey.

BACKGROUND: The rapid introduction of teleworking due to the coronavirus disease 2019 pandemic has led to concerns about increases in cyberbullying (CB) worldwide. However, little is known about workplace CB in non-Western countries. The first objective was to clarify the prevalence and characteristics regarding workplace CB victimization in Japan. The second objective was to demonstrate the psychological outcomes of CB victimization in combination with traditional bullying (TB). METHODS: We conducted an anonymous, cross-sectional, Internet-based survey targeting regular employees in Japan (N = 1200) in January 2021. We investigated CB victimization using the Inventory of Cyberbullying Acts at Work and TB victimization by using the Short Negative Act Questionnaire. Possible explanatory factors for TB/CB victimization were sociodemographic variables, personality trait, chronic occupational stress, organizational climate, and gratitude at work. We also measured psychological distress, insomnia, and loneliness to assess adverse effects of workplace bullying. Two-step cluster analysis was used in determining the patterns combined with TB and CB victimization. Hierarchical binomial logistic regression analysis was used. RESULTS: In total, 8.0% of employees reported experiencing CB on a weekly basis. CB victimization was associated with younger age, managerial position, higher qualitative workload, and active information dissemination via the Internet, and frequency of teleworking. Three clusters based on TB and CB victimization patterns were identified: those who belong to the first cluster suffered neither from TB and CB (81.0%), the second cluster suffered only from TB (14.3%), and the third cluster suffered from both TB and CB (4.8%). The third cluster exhibited higher odds ratios (ORs) and 95% confidence intervals (CIs) for psychological distress (OR = 12.63, 95% CI = 4.20-38.03), insomnia (OR = 6.26, 95% CI = 2.80-14.01), and loneliness (OR = 3.24, 95% CI = 1.74-6.04) compared to the first cluster. CONCLUSIONS: These findings firstly clarify the prevalence and correlated factors of CB victimization among employees in Japan. Further, we showed that psychological wellbeing can be impaired by the coexistence of TB and CB. Our research could be the first step to develop the effective countermeasures against workplace CB.

Ibaraki's Amabie-chan usage and its association with infection prevention behavior and fear of COVID-19: a cross-sectional preliminary survey of the Tsukuba Salutogenic Occupational Cohort Study.

BACKGROUND: Ibaraki's Amabie-chan is a COVID-19 infection control system unique to Ibaraki prefecture, Japan. It requires residents to register each time they visit events, commercial facilities, and restaurants. The number of registrations has been limited, and its function alerting about people positive for COVID-19 infection seems not to be working. Nevertheless, registration with the system might have some impact on the user's behavior. In the current preliminary survey, the possible impact of Ibaraki's Amabie-chan on infection prevention behavior and fear of COVID-19 was investigated. METHODS: A cross-sectional, web-based, anonymous, and self-administered survey was conducted at two workplaces in Tsukuba Science City, Ibaraki, Japan. The first survey was conducted at one of the workplaces in November 2020, and the second survey, at the other workplace in February 2021. Variables of interest were sex, age group, marital status, employment status, Ibaraki's Amabie-chan use, COVID-19 Contact-Confirming Application use, ten items of infection prevention behaviors, and fear of COVID-19. Hierarchical linear regression analysis was performed. RESULTS: In both surveys, use of Ibaraki's Amabie-chan was significantly associated with COCOA use and with "physical condition management such as body temperature measurement." No association was found with other infection prevention behaviors or with fear of COVID-19. CONCLUSIONS: Our findings did not provide sufficient evidence for the effectiveness of Ibaraki's Amabie-chan in regard to users' infection control behavior. Further detailed study is needed to investigate the effectiveness in terms of infection prevention and the cost-effectiveness of Ibaraki's Amabie-chan.

Morning preference is associated with subjective happiness among Japanese female workers: A moderation analysis by sleep characteristics from the SLEPT study.

Research on mental health in working populations has predominantly focussed on negative outcomes, while studies on the positive aspects of life remain very limited, especially in Japan. Although morningness has recently been considered a factor for being happy, the role of sleep characteristics as it relates to the association between morningness and happiness has not been substantiated. The aim of this study is to investigate the associations between diurnal preference and level of subjective happiness in healthy, full-time, daytime workers in Japan. We also tested the moderation effect of sleep parameters on the relationship between diurnal preference and subjective happiness. This is an exploratory analysis from the cross-sectional data of the SLeep Epidemiology Project at the University of Tsukuba (SLEPT Study). Subjective happiness was evaluated using a single-item question. Diurnal preference was assessed using the Morningness-Eveningness Questionnaire (MEQ), in which higher scores indicate greater tendency to have morning preference. The participants underwent assessment of sleep parameters for 7 consecutive days using a waist-worn actigraphy device and kept a sleep diary. Sleep parameters investigated were subjective sleep quality, sleep disturbance, daytime sleepiness, weekend oversleep, total sleep time, sleep onset time, wake time, and sleep efficiency. A total of 205 males (average 42.6 ± 10.4 years) and 272 females (41.1 ± 9.8 years) were eligible for analysis. Hierarchical liner regression analysis was used to show the relationships of subjective happiness with MEQ score, and the sleep parameters. Further, moderation analysis was conducted by adding the interaction between MEQ score and the sleep parameters. After adjusting for age, psychological distress, self-rated health, and occupational stress, we found that subjective happiness was significantly associated with higher MEQ score and sleep efficiency but only in female. The moderating role of sleep parameters was not found. We discussed the implications of the obtained results and a possible strategy to maintain and improve subjective happiness of female workers who have evening preference.

Comparison of predicted psychological distress among workers between artificial intelligence and psychiatrists: a cross-sectional study in Tsukuba Science City, Japan.

OBJECTIVES: Psychological distress is a worldwide problem and a serious problem that needs to be addressed in the field of occupational health. This study aimed to use artificial intelligence (AI) to predict psychological distress among workers using sociodemographic, lifestyle and sleep factors, not subjective information such as mood and emotion, and to examine the performance of the AI models through a comparison with psychiatrists. DESIGN: Cross-sectional study. SETTING: We conducted a survey on psychological distress and living conditions among workers. An AI model for predicting psychological distress was created and then the results were compared in terms of accuracy with predictions made by psychiatrists. PARTICIPANTS: An AI model of the neural network and six psychiatrists. PRIMARY OUTCOME: The accuracies of the AI model and psychiatrists for predicting psychological distress. METHODS: In total, data from 7251 workers were analysed to predict moderate and severe psychological distress. An AI model of the neural network was created and accuracy, sensitivity and specificity were calculated. Six psychiatrists used the same data as the AI model to predict psychological distress and conduct a comparison with the AI model. RESULTS: The accuracies of the AI model and psychiatrists for predicting moderate psychological distress were 65.2% and 64.4%, respectively, showing no significant difference. The accuracies of the AI model and psychiatrists for predicting severe psychological distress were 89.9% and 85.5%, respectively, indicating that the AI model had significantly higher accuracy. CONCLUSIONS: A machine learning model was successfully developed to screen workers with depressed mood. The explanatory variables used for the predictions did not directly ask about mood. Therefore, this newly developed model appears to be able to predict psychological distress among workers easily, regardless of their subjective views.

Differences in psychological distress between managers and non-managers in female workers: a cross-sectional study in Tsukuba Science City, Japan.

The Japanese government has made efforts towards the advancement of women into society; thereby, the proportion of female managers has been increasing. Recent reports have shown that managers tend to be in poor health condition. However, little research has been conducted to examine the psychological health of female managers. Therefore, the aim of our study was to reveal the difference of psychological distress by occupational position in female workers with focus on occupational stress. A cross-sectional survey was conducted in 2017 via an anonymous, self-administered questionnaire distributed to workers in Tsukuba City, Japan. Student unpaired t test was used to compare occupational stress and psychological distress by occupational position. Binomial logistic regressions were used to analyze factors that affect psychological distress separately in managers and non-managers. A total of 1543 women (168 managers, 1375 non-managers) were analyzed. Managers showed higher occupational stress but lower psychological distress than non-managers. Problems in interpersonal relationships was positively associated with psychological distress, whereas occupation as a researcher/academic was negatively associated with psychological distress in managers. Mental workload and problems in interpersonal relationships were positively associated with psychological distress, whereas reward from work and support were negatively associated with psychological distress in non-managers. Managers and non-managers both showed an association between psychological distress and problems of interpersonal relationships. Non-managers might have higher psychological distress due to lower reward from work. It is important to increase reward from work and to develop female workers' interpersonal skills in order to reduce the psychological distress of female workers.

Protein intake in inhabitants with regular exercise is associated with sleep quality: Results of the Shika study.

STUDY OBJECTIVES: Although associations between sleep quality and environmental factors and nutrient intake have been reported, interactions between these factors have not been elucidated in detail. Therefore, this cross-sectional study examined the effects of regular exercise and nutrient intake on sleep quality using the Pittsburgh Sleep Quality Index (PSQI), which is the most frequently used index for sleep evaluation. METHODS: The participants included 378 individuals aged 40 years or older living in Shika Town, Ishikawa Prefecture. Of these individuals, 185 met the inclusion criteria. The participants completed a self-administered questionnaire assessing lifestyle habits and frequency and duration of exercise, the PSQI, and the brief-type self-administered diet history questionnaire (BDHQ) on nutrient intake. RESULTS: A two-way analysis of covariance on regular exercise and PSQI scores indicated that protein intake (17.13% of energy) was significantly higher in the regular exercise and PSQI ≤10 groups than in the non-regular exercise or PSQI ≥11 groups (p = 0.002). In a multiple logistic regression analysis with PSQI scores (≤10 and ≥11), protein intake was a significant independent variable in any of the models adjusted for confounding factors such as age, sex, body mass index, current smoker, and current drinker (OR: 1.357, 95% CI: 1.081, 1.704, p = 0.009) in the regular exercise group but not in the non-regular exercise group.Conclusions We identified a positive relationship between sleep quality and protein intake in the regular exercise group. These findings suggest that regular exercise at least twice a week for 30 minutes or longer combined with high protein intake contributes to good sleep quality.

Prefrontal activation while listening to a letter of gratitude read aloud by a coworker face-to-face: A NIRS study.

Near-infrared spectroscopy (NIRS) is a non-invasive functional brain imaging technique. NIRS is suitable for monitoring brain activation during social interactions. One of the omnipresent social interactions for employees is saying thank you and being thanked. It has been demonstrated that expressing and receiving gratitude leads to employees' well-being and performance. To date, there have been no neuroimaging studies that monitor brain activity when receiving gratitude. Thus, we designed an experiment using NIRS to monitor brain function while listening to a letter of gratitude read by a coworker. We hypothesized that listening to a letter of gratitude read aloud by a co-worker in a face-to-face setting would have different effects on PFC activity than listening to a conversation about a neutral topic. We recruited 10 pairs of healthy right-handed employees. They were asked to write a letter of gratitude to their partner 1 week before the experiment. In the experiment, each pair sat face-to-face and read their letters aloud to each other. We evaluated changes in mood state before and after the experiment. NIRS was measured in each participant while they listened to their peers in the experimental condition (gratitude letter) and control condition (talking about the weather and date). The results suggested that negative mood state decreased after the experiment. Moreover, there were interaction effects between conditions and periods. Although further studies are needed to confirm the interpretation, our findings suggested that experience of being thanked was accompanied by prefrontal cortex activation.

Relationships between insomnia, long working hours, and long commuting time among public school teachers in Japan: a nationwide cross-sectional diary study.

OBJECTIVES: The present study aimed to clarify the prevalence and risk factors of insomnia among public school teachers in Japan by examining the relationships between working hours, commuting time, and insomnia. Time spent on work activities among teachers with insomnia was also investigated. METHODS: This study was a secondary analysis of data obtained in a 2016 survey of working conditions among public elementary/junior high school teachers in Japan. A total of 11,390 teachers (women: 47.4%, average age: 42.2 ± 11.3 years) were selected for analysis. The relationships between working hours, commuting time, and insomnia were evaluated using a binomial logistic regression model. The primary outcome was insomnia, defined by a score of ≥6 on the Athens Insomnia Scale. Explanatory factors were working hours/week, commuting time/day, six subscales of occupational stress, age group, presence of children, type of job, type of the school, and the urbanicity of the school. RESULTS: In total, 41.7% of men and 44.0% of women were classified into the insomnia group. The insomnia group spent more time preparing for lectures, and a significant association was observed between insomnia and long working hours and commuting time. Results of multivariate logistic regression analysis showed that long working hours, long commuting time, and urbanicity of the school were statistically significantly associated with insomnia. CONCLUSIONS: Insomnia is common among public school teachers in Japan. Our findings suggest the importance of reducing the time spent on working to prevent insomnia.

School Ijime (Bullying) Experience Is a Possible Risk Factor for Current Psychological Distress among Science City Workers: A Cross-Sectional Study in Tsukuba, Japan.

Early-life adversities are considered to have long-term impact on health. There have been many studies regarding the experience of being bullied and its harmful psychological influence, but such influence on workers remains to be investigated in Japan. We therefore aimed to examine the prevalence of workers with experiences of being bullied or bullying others during childhood and adolescence and to clarify the relation between those experiences and current psychological distress. A cross-sectional study using an anonymous self-report web questionnaire was conducted in November 2017. The study population was 19,481 workers belonging to the Tsukuba Science City Network, and we analyzed the data of 6,015 participants (3,715 men and 2,300 women, aged between 20 years and 59 years). The percentages of participants with experiences of being bullied were 51.5% for men and 56.2% for women; those with experiences of bullying others were 36.5% of men and 29.4% of women. Relations between experiences of bullying and psychological distress were assessed using Chi-squared tests. Logistic regression analyses with psychological distress as an objective variable and experiences of bulling as explanatory variables were performed using those who had no bulling experiences as control. In both men and women, experiences of being bullied were significantly associated with psychological distress after adjustment socioeconomic factors (the odds ratios were 1.26 for men (95% CI = 1.05-1.52) and 1.72 for women (95% CI = 1.39-2.13)). Consideration of past social experiences, such as being bullied, is useful for mental health management among workers reporting psychological distress.

Association between flourishing mental health and occupational stress among workers of Tsukuba Science City, Japan: a cross-sectional study.

BACKGROUND: Flourishing, defined as the coexistence of hedonic and eudaimonic well-being, is the most favorable end of the mental health spectrum. A growing body of evidence has demonstrated the association between flourishing mental health and favorable work-related outcomes. However, epidemiology of flourishing mental health is scarce in Japan. Moreover, the relationship between flourishing mental health and occupational stress has not been elaborated. Therefore, the aim of this study was to elucidate (1) the prevalence of flourishing mental health and (2) the association between flourishing mental health and occupational stress among Japanese workers. METHODS: The present survey was conducted in from February to March 2017 via an anonymous, self-administered, and web-based questionnaire among workers in Tsukuba Science City, Japan. Mental Health Continuum Short Form was used to assess flourishing mental health. We performed binomial logistic regression analyses to calculate the adjusted odds ratios (AOR) and 95% confidence intervals (CI) of occupational stress for flourishing mental health, controlling for sociodemographic factors. RESULTS: A total of 7012 respondents (4402 men, 2610 women) were analyzed. The overall prevalence of flourishing mental health among the respondents was 12.4%. Full-time (permanent) workers were less likely to be flourishing. Reward from work (AOR = 2.34, 95% CI = 2.04-2.68), support from colleagues and superiors (AOR = 1.67, 95% CI = 1.44-1.94), and workload (AOR = 1.19, 95% CI = 1.05-1.36) were positively associated with flourishing mental health, whereas mental workload (AOR = 0.65, 95% CI = 0.57-0.75) was inversely associated with flourishing mental health. CONCLUSIONS: The findings of the present study shed light on the association between flourishing mental health and occupational stress.

Non-Regular Employment Status Is Associated with Psychological Distress among Young Researchers: A Cross-Sectional Study in Tsukuba, Japan.

Non-regular employment is increasing and its mental health impact is a globally important problem. In Japan, non-regularly employed researchers are increasing, especially within young age groups, because employment quotas were not sufficiently expanded against rapid increasing number of doctorate holders. It is therefore important to understand the relationship between non-regular employment and mental health. The significance of our research is to contribute to the improvement of researchers' mental health by clarifying the influence of employment status on psychological distress. We conducted a cross-sectional, web-based survey in 2017 via an anonymous, self-administered questionnaire distributed to workers in Tsukuba Science City, Japan. The survey questionnaire items included employment status, psychological distress, occupational stress, sex, age, and income. We analyzed 2,762 valid responses in two categories (1,850 regular employment, 912 non-regular employment) and two subcategories based on age according to the definition of "young researcher" by the Ministry of Health, Labor and Welfare (20-39 years vs. 40-59 years). Psychological distress was defined as a total K6 score of 5 or greater. Binomial logistic regression was used to calculate odds ratios and 95% confidence intervals for psychological distress. Non-regular employment was significantly associated with psychological distress in the age 20-39 group but not in the age 40-59 group. At the age 20-39 group, a negative association was shown between psychological distress and reward from work (i.e., pride in their job, ability utilization, and sense of accomplishment). Support to increase psychological work rewards may be important in reducing psychological distress for young non-regularly employed researchers.

Relationship between suicidal ideation and family problems among young callers to the Japanese crisis hotline.

Previous studies have reported an association between family relationships and suicidal behavior, and found that people with high suicidal ideation are not likely to consult with others about their distress. An effective consulting service is therefore necessary for such individuals. Crisis hotlines are effective for reducing suicide risk, but their associated suicide ideation rate and odds ratio of family problems children remain unclear. The present study investigated the suicidal ideation rate and odds ratio of callers under 20 years of age (N = 24,333) with family problems to the Japanese crisis hotline in 2012. There were 5,242 (21.5%), 18,061 (74.2%), and 1,030 (4.2%) calls related to family problems, other problems, and both, respectively. The suicidal ideation rate and odds ratio of callers with family problems were 2.2% and 0.426, respectively. This result suggested that callers with family problems have a significantly lower rate and odds ratio for suicidal ideation compared with others. However, some associations with a high suicide ideation rate were found for individual items among callers with family problems such as abuse (20.4%), family breakdown (16.1%), and domestic violence (10.6%). Further studies are needed to understand the suicidal ideation of callers with family problems and develop more effective preventive strategies.

Relationship between workplace social capital and suicidal ideation in the past year among employees in Japan: a cross-sectional study.

BACKGROUND: A growing body of evidence has demonstrated the associations between social capital and health. In residential or geographical areas, social capital has attracted attention for its protective effects against suicide. However, to this date, the relationship between social capital and suicidal ideation is not fully elaborated in the occupational setting. Therefore, the aim of the present study was to examine the association between workplace social capital and suicidal ideation in the past year among employees in Japan. METHODS: A cross-sectional, web-based survey was conducted in February/March 2017 via an anonymous self-administered questionnaire distributed to workers in Tsukuba Science City, Japan. Binomial logistic regressions were used to calculate the odds ratios (ORs) and 95% confidence intervals (CIs) for suicidal ideation in the past year, controlling for age group, marital status, educational attainment, and annual household income. The results were shown stratified by sex and occupation. RESULTS: In total, 7255 of 19,481 workers responded, out of which we could analyze 6325 responses (4030 men, 2295 women). The prevalence of suicidal ideation in the past year was 5.9% for men and 7.8% for women. Low workplace social capital was statistically significantly associated with suicidal ideation both for men (OR = 2.57, 95% CI = 1.72-3.83) and for women (OR = 1.75, 95% CI = 1.15-2.66), compared with high workplace social capital after controlling for socioeconomic factors. CONCLUSION: Higher workplace social capital was associated with a reduced risk of suicidal ideation in the past year. Promoting workplace social capital could contribute to preventing suicide among employees in Japan.

Characteristics of Telephone Crisis Hotline Callers with Suicidal Ideation in Japan.

Hotline callers do not always have suicidal ideation and previous studies have noted that the rate of such callers is limited. Crisis hotline counselors must be able to identify high-risk callers in order to provide appropriate support. This study investigated the characteristics of Japanese crisis hotline callers in 2012 (N = 541,694) and is the first to analyze crisis hotline data for all parts of Japan over 1 year. About 14% of the callers had suicidal ideation and 6% had a history of attempted suicide. The odds ratio for suicidal ideation among those with a history of attempted suicide was 15.5. The suicidal ideation rate was much smaller compared to previous studies in other countries. There is a psychological barrier that must be broken for high-risk people to use support hotlines. In addition, attempted suicide is a strong exclusive predisposing factor for death due to suicide; therefore, counselors should pay careful attention to callers with a history of attempted suicide. The characteristics of Japanese crisis hotline callers and the features of suicidal ideation revealed in the present study are expected to be useful in developing telephone crisis hotline strategies.

Absenteeism due to mental health problems and systems for return to work: an internet-based unmatched case-control study.

PURPOSE: The aim of this study was to investigate the risk factors for absenteeism due to mental health problems with regard to company characteristics and systems for return to work in Japan. METHODS: This was an Internet-based unmatched case-control study. Two hundred and fifty-eight workers who experienced over 28 days of sick leave due to mental health problems (cases) and 258 workers who have not taken sick leave (controls) were recruited. Company characteristics and the awareness and presence of systems for return to work were analysed as indicators of absenteeism. RESULTS: A total of 501 workers were included in the analysis. Females were less likely to experience absenteeism when adjustments were made for both the awareness and presence of systems [odds ratio (OR) = 0.51 and 0.41, respectively]. Large companies showed an increased risk of having absentee workers than small companies. The awareness of a gradual resumption system and the presence of a sick pay system were related to absenteeism (OR = 2.75 and 2.40, respectively). CONCLUSIONS: The awareness and presence of systems for return to work are related to the long-term absenteeism. The predictors of sex and company size are also related to the experience of the long-term absenteeism. To understand the effect of systems for return to work on absenteeism due to mental problems, further studies are needed.

Risk Factors for Suicidal Ideation Among Telephone Crisis Hotline Callers in Japan.

BACKGROUND: Telephone hotlines are a widely used type of suicide prevention program. AIMS: The aim of this study was to clarify the risk factors for suicidal ideation by investigating its association with a number of characteristics among telephone hotline callers. METHOD: Data were collected over a 10-year period from a total of 246,595 calls to Inochi No Denwa, a telephone crisis hotline in Ibaraki, Japan, and subsequently analyzed. Odds ratios for suicidal compared with nonsuicidal ideation were also calculated. RESULTS: About 6% of the calls to the hotline were suicide related, and about 2% of the callers had attempted suicide in the past. Odds ratios for suicidal ideation increased during winter, but no daily tendencies were evident. Those whose problems were related to their way of life were at the highest risk of suicidal ideation, followed by those with health-related concerns. CONCLUSION: We were able to identify risk factors for suicidal ideation based on an analysis of enormous amounts of data from a telephone crisis hotline in Japan. Knowledge of these risk factors is expected to lead to improvements in suicide prevention programs.

A survey of support systems for return to work in Japanese companies: a cross-sectional study.

The present study aimed to survey systems in Japanese companies for supporting workers returning to work from sickness absence due to mental illness. A questionnaire survey was mailed to 3,545 companies. Support systems for return to work, sick leave, and multiple sick-listed (MSL) workers were examined. A total of 161 companies responded to the survey (response rate: 4.5%). About 80% of the companies expressed difficulty in dealing with workers with mental health problems. About half of all companies reported having reset period and financial compensation systems, as well as gradual resumption and trial attendance systems. Most large companies tended to have reset period and trial attendance systems. No association was found between company size and MSL rates. The most frequent diagnosis among workers was depression, and the mean number of sick leave days was 275.3. Although there might have been a selection bias due to the low response rate, the results of this study are expected to be useful for companies when formulating employment systems.

Relationship between sickness presenteeism and awareness and presence or absence of systems for return to work among workers with mental health problems in Japan: an Internet-based cross-sectional study.

OBJECTIVES: The objective of this study was to clarify the relationship between sickness presenteeism and the degree of awareness of company regulations regarding financial compensation for absenteeism. METHODS: An Internet-based survey of 258 full-time workers who had more than 28 days of sickness absence due to mental health problems was conducted. Workers were categorized as having either low or high sickness presenteeism, and awareness and presence or absence of systems for return to work and duration of financial compensation were compared between groups. RESULTS: The following factors were significantly related to high sickness presenteeism based on logistic regression analyses: working for a private company (odds ratio [OR]=2.57; 95% confidence interval [CI]=1.10-5.99); recognition of a gradual resumption system (OR=3.89, 95% CI=1.02-14.81); and awareness regarding the duration of financial compensation (OR=1.04, 95% CI=1.01-1.07). CONCLUSIONS: No relationship was found between mental sickness presenteeism and presence or absence of systems for return to work in our multivariate analysis; however, a relationship was apparent between sickness presenteeism and characteristics of the workers' companies. These results are expected to contribute to research involving human resources and occupational health.