Journal List > Korean J Occup Environ Med > v.24(4) > 1125603

Heo, Kim, Lee, Jo, Jang, Kim, and Kim: An Association between Working Schedules and Depression in Public Sector Employees



This study determined the work schedules of public project workers who work an irregular shift and assessed the effect of these schedules on depression.


Study subjects were 2934 laborers who are members of seven labor unions. Each was given a questionnaire requesting basic personal information, habits, socioeconomic status, and work schedules. Information gathered on work schedules included daytime, nighttime, and weekend work hours. Depression was evaluated using the Beck Depression Inventory (BDI), with Laborers who checked "not depressed" and "slightly depressive" categorized to a low-risk group, whereas laborers who checked "depressed" and "severely depressed" were categorized to a high-risk group. We used the Chi-square test and multivariate logistic regression to examine associations between work schedules and depression.


Laborers on an irregular work schedule averaged 47.8 hours/week and laborers who working over 48 hours/week comprised over half (54.5%) of the total population. Laborers performing night work, Sunday work, and Saturday work more than once in a month made up 25.7%, 30.8% and 33.5% of the examined population, respectively. A high-risk for depression was identified in 10.4% of laborers. Using logistic regression, depression was statistically associated with working : over 10 hours a day (OR=1.63, 95% CI 1.10~2.43), night work (OR=2.20, 95% CI 1.46~3.32), Sunday work (OR=1.81, 95% CI 1.15~2.85) and Saturday work (OR=1.82 95% CI 1.18~2.82).


A significant number of laborers with irregular working shifts work long hours and on weekends. Depression was significantly associated with this type of work schedule.

Figures and Tables

Table 1
General characteristics of subjects by gender N (%)
Table 2
Working hours by gender (Mean±Standard Deviation), N(%)

*by chi-square test.

working at least 2 hours from 10pm to 5am.

working at least 2 hours from 6pm to 10pm.

Table 3
General characteristics and Beck's depression index (BDI -II) N(%)

*by chi-square test.

not + mild.

moderate + severe.

Table 4
Working hours and Beck's depression index (BDI -II) N(%)

*by chi-square test.

not + mild.

moderate + severe.

Table 5
Result of multiple logistic regression tests for Beck's depression index and working hours (Odds ratios, 95% confidence interval)

Calculated by logistic regression analysis.

*p < 0.05.

Adjusted for sex, age, education, branches, locals, employment type, income satisfaction, smoking, alcohol drinking.


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