key: cord-1023355-t3u213mg authors: Eguchi, H.; Inoue, A.; Hino, A.; Tsuji, M.; Tateishi, S.; Ikegami, K.; Nagata, T.; Matsugaki, R.; Fujino, Y.; project, The CORoNaWork title: Effect of working from home on the association between job demands and psychological distress date: 2022-03-13 journal: nan DOI: 10.1101/2022.03.10.22272174 sha: bca66299f98392adb02366a1ae920cafc5b3da7f doc_id: 1023355 cord_uid: t3u213mg Purpose Limited information is available about the association between workplace psychosocial factors and general mental health status among workers during the COVID-19 pandemic. This study examined how working from home affected the association between job demands and psychological distress (PD). Method A cross-sectional online survey was conducted in December 2020 (N=27,036). The dependent variable (PD) was assessed using the Kessler Psychological Distress Scale. Job demands were assessed using the Job Content Questionnaire. Working from home was determined by participants' responses to the question: Do you currently work from home? We used a two-level regression analysis adjusted for prefecture; each individual-level variable at level 1 was nested into each prefecture at level 2, stratified by working from home or not. Results Overall, 21.3% of participants worked from home. The interaction between working from home and job demands was significant. Job demands were positively associated with PD. The stratified analysis showed the associations were weaker among employees who worked from home compared with those who did not. Conclusion The association between job demands and PD may be weakened by working from home. The ongoing coronavirus disease 2019 pandemic poses a threat to psychological health. 2 Previous research revealed profound and wide ranging psychosocial impacts at the individual, 3 community, and international levels during past outbreaks of infectious diseases (Mukhtar 2020). 4 The current health crisis has had unprecedented impacts on workplace practices. A cross-sectional online survey was conducted in December 2020 among participants who had 3 8 previously registered with a Japanese web survey company. Invitations to participate were sent to 3 9 665,381 registrants via email. Details of the survey protocol have previously been reported (Fujino et 4 0 al. 2021). A sampling plan was designed to recruit an equal number of respondents from 20 4 1 collection units comprising a combination of five regions each, with comparable sex and office/non-4 2 office worker status. The target sample size was 1,500 respondents from each collection unit, giving 4 3 a total of 30,000 respondents. In total, 1,650 respondents (target sample size plus a margin of 10%) 4 4 were recruited from each collection unit. Of the 33,302 eligible respondents, 215 were excluded 4 5 because they were deemed to have provided fraudulent responses by Cross Marketing Inc., leaving 4 6 33,087 respondents. Participants were selected using a random number generator. The study 4 7 population comprised individuals interested in participating in a survey. There was a modest 4 8 financial incentive for survey participation (equivalent to a few US dollars). We excluded 6,051 4 9 surveys with invalid responses or response errors, leaving 27,036 surveys for analysis in this study. The exclusion criteria were: extremely short response time (≤6 minutes), extremely low body weight 5 1 (<30 kg), extremely short height (<140 cm), inconsistent answers to similar questions throughout the 5 2 survey (e.g., inconsistent responses to questions about marital status and living area), and incorrect 5 3 answers to a staged question used to identify fraudulent responses (i.e., "Choose the third-largest 5 4 number from the following five numbers"). 5 5 The study aims and protocol were approved by the Ethics Committee of Medical Research, 5 7 University of Occupational and Environmental Health, Japan (R2-079). Informed consent to 5 8 participate in this study was obtained from all participants. Participants were informed in advance 5 9 that their participation was strictly voluntary and all information they provided would remain 6 0 confidential. Individuals who consented to participate were able to access a designated website (after 6 1 confirmation of their personal information) where they could complete the survey. Participants had 6 2 the option to not respond to any part of the questionnaire and could discontinue participation at any 6 3 time. 6 4 6 5 Dependent variable: psychological distress 6 6 Psychological distress was assessed using the Kessler Psychological Distress Scale (K6). The K6 6 7 was originally developed as a screening instrument for non-specific psychological distress and 6 8 serious mental illness. Its internal reliability and validity have been documented (Furukawa et al. 2008). The K6 comprises a six-item battery asking how frequently respondents had experienced 7 0 specific symptoms of psychological distress in the past 30 days. Responses range from 0 (none of 7 1 the time) to 4 (all of the time), giving a total score of 0-24. The K6 has been translated into Japanese, 7 2 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted March 13, 2022. ; and the Japanese version has been validated. In this sample, the Cronbach's α coefficient for the K6 7 3 was 0.88. 7 4 7 5 Independent variable: Job demands 7 6 We used the job demands scale from the Japanese version of the Job Content Questionnaire (JCQ) 7 7 ( Kawakami et al. 1995) . The JCQ was developed by Karasek and is based on the job demands-7 8 control (or demand-control-support) model. It contains five items that assess job demands, rated on 7 9 a 4-point scale (1 = strongly disagree to 4 = strongly agree). The total score was calculated according 8 0 to the JCQ User's Guide (score range: 12-48) (Karasek et al. 1998) . The Japanese version of the 8 1 JCQ had acceptable reliability and validity (Kawakami et al. 1995) . In the present study, the 8 2 Cronbach's α coefficient for job demands was 0.68. 8 3 8 4 Moderator variable: working from home 8 5 Working from home was determined by participants' responses to the question: "Do you currently 8 6 work from home?" Response options were "More than 4 days per week," "More than 2 days per 8 7 week," "Less than 1 day per week," and "Hardly ever." Responses were subsequently dichotomized 8 8 using a two-point scale: 0 = yes ("More than 4 days per week," "More than 2 days per week," "Less 8 9 than 1 day per week"); and 1 = no ("Hardly ever"). 9 0 9 1 Assessment of covariates 9 2 Covariates were measured using a self-administered questionnaire and included demographic and 9 3 lifestyle characteristics such as sex, age, marital status, educational attainment, occupation, job type, 9 4 annual family income, and company size. Age was expressed as a continuous variable. Marital status 9 5 was classified into three categories: married, divorced/widowed, and unmarried. Educational 9 6 attainment was classified into three categories: junior high school and high school, college and 9 7 technical school, and university and graduate school. Occupation was classified into 10 categories: 9 8 staff member; manager; executive; public official/teaching staff/non-profit organization employee; 9 9 temporary and contract employee; self-employed person; small office/home office worker; 1 0 0 agriculture, forestry, and fishery worker; professional (e.g., lawyer, accountant, medical doctor); and 1 0 1 others. Job type was classified into three categories: mainly desk work (clerical or computer work), 1 0 2 mainly talking to people (e.g., customer service, sales, selling), and mainly labor (e.g., work at 1 0 3 construction sites, physical work, nursing care). Participants were asked to indicate their yearly 1 (self-employment), 2-4, 5-9, 10-29, 30-49, 50-99, 100-499, 500-999, 1,000-9,999, and ≥ 10,000 1 0 8 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted March 13, 2022. ; https://doi.org/10.1101/2022.03.10.22272174 doi: medRxiv preprint employees. The cumulative incidence rate of COVID-19 infection 1 week before the survey in the 1 0 9 residential prefectures was used as a prefecture-level variable. This information was collected from 1 1 0 the websites of public institutions. 1 1 1 1 1 2 Statistical analyses 1 1 3 Student's t-tests and chi-square tests were used to examine differences in demographic variables and 1 1 4 psychological distress between participants who were working from home and those who were not. 1 1 5 We used multilevel regression analyses with two levels adjusted for the prefectural level, whereby 1 1 6 each individual-level variable at level 1 was nested into each prefecture at level 2. Examination of 1 1 7 the interaction between working from home and job demands showed a significant interaction (p = 1 1 8 0.02). To compare the adjusted coefficients by presence or absence of working from home, multiple 1 1 9 regression analyses were used to examine the association between job demands and psychological 1 2 0 distress stratified by availability of telecommuting. We conducted multiple regression analysis using 1 2 1 a crude model (Model 1) and a model adjusted for sex, age, marital status, educational attainment, 1 2 2 occupation, job type, annual household income, and company size (Model 2). All analyses were 1 2 3 performed using Stata 15SE (StataCorp, College Station, TX, USA), with statistical significance set 1 2 4 at p < 0.05. 1 2 5 1 2 6 Results 1 2 7 Approximately 20% of participants had the opportunity to work from home. Employees who worked 1 2 8 from home were older and had lower psychological distress than those who did not work from home. 1 2 9 Men, self-employed people, those with a higher household income, those whose job mainly involved 1 3 0 desk work, and employees in large companies were more likely to work from home (Table 1) . Table 1 here ---1 3 3 1 3 4 We demonstrated a significant association between job demands and psychological distress (p < 1 3 5 0.05). The stratified analysis (post hoc simple slope analysis) showed that the effect of job demands 1 3 6 on psychological distress was weaker among employees who worked from home (coefficient = 0.15) 1 3 7 than among those who did not (coefficient = 0.18) ( Table 2) . Company size was positively associated 1 3 8 with psychological distress among those who worked from home, and negatively associated with 1 3 9 psychological distress among those who did not work from home. Table 2 here ---1 4 2 1 4 3 Discussion 1 4 4 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. We conducted a large online survey on December 22, 2020, just before the government declared a 1 4 5 second state of emergency in the greater Tokyo area (January 7, 2021). Men, self-employed people, 1 4 6 those with a higher household income, those whose job mainly involved desk work, and employees 1 4 7 in large companies were more likely to work from home. The association between job demands and 1 4 8 psychological distress was stronger among employees who did not work from home than among 1 4 9 those worked from home. 1 5 0 1 5 1 Working from home may weaken the association between job demands and psychological distress. 1 5 2 Working from home has been associated with reduced commuting time and costs, reduced 1 5 3 environmental pollution, and the opportunity to support family duties (e.g., picking up children from 1 5 4 school), which may be desirable for many workers (Kotera and Correa Vione 2020). Having a sense 1 5 5 of control over worktime can also help employees manage their work-life balance (Beckers et al. previous study showed that the association between job demands and psychological distress may be The effect of company size on psychological distress differed between those who worked from home 1 6 5 and those that did not. The association between company size and psychological distress in previous 1 6 6 studies was inconsistent (Inoue et al. 2010; Kanamori et al. 2020 This study had some limitations. First, our study population required Internet access to complete the 1 7 4 survey and therefore might have comprised participants that were more aware of COVID-19 1 7 5 infection through access to online information. People should be aware of the psychological risk of 1 7 6 too much media exposure and control their access in health crises such as the COVID-19 outbreak 1 7 7 (Sasaki et al. 2020). Our results are not completely generalizable to individuals without Internet 1 7 8 access or to people in other countries and settings. Second, we had no information about participants' 1 7 9 personality traits. In addition, we had no information about the number of confirmed cases of 1 8 0 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted March 13, 2022. ; COVID-19 in the workplace. Further studies are needed to evaluate whether other confounding 1 8 1 factors provide possible mechanisms for the observed attenuation in the associations between job 1 8 2 demands, working from home, and psychological distress. Third, this study used a cross-sectional 1 8 3 design, and no causal associations could be determined. A further study using an interventional or 1 8 4 prospective design is needed to clarify potential causal associations between job demands, working 1 8 5 from home, and psychological distress in the Japanese working population. Finally, we should 1 8 6 consider the possible effects of common method bias when interpreting the results. 1 8 7 The association between job demands and psychological distress may be weakened by working from 1 9 0 home. 1 9 1 All rights reserved. No reuse allowed without permission. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The copyright holder for this preprint this version posted March 13, 2022. 1 4 (which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. Adjusted for sex, age, marriage, educational attainment, occupation, job type, annual household income, and company size CI, confidence interval 1 9 2 Amano H, Fukuda Y, Shibuya K, Ozaki A, Tabuchi T (2021) Factors associated with the work 1 9 3 engagement of employees working from home during the COVID-19 pandemic in Japan. Int J 1 9 4Environ Res Public Health 18 (19)