Table 1. Baseline characteristics of the study participants among 1810 Japanese employees in 2005.
| total | Q1 | Q2 | Q3 | Q4 | ||
| Number of participants | 1810 | 446 | 475 | 422 | 467 | |
| Male, n (%) | 1362 (75.2) | 337 (75.4) | 377 (79.6) | 309 (73.5) | 339 (72.3) | 0.070 |
| Age, mean±SD | 35.6±8.5 | 35.8±8.9 | 35.8±8.7 | 36.1±8.6 | 34.8±7.8 | 0.081 |
| Work hours per day, mean±SD | 9.6±5.2 | 9.5±5.7 | 9.8±6.9 | 9.5±4.4 | 9.7±2.7 | 0.651 |
| Administrative post, n (%) | 767 (42.4) | 192 (43.0) | 197 (41.5) | 184 (43.6) | 194 (41.5) | 0.889 |
| Marriage, n (%) | 905 (50.0) | 246 (55.2) | 244 (51.4) | 209 (49.5) | 206 (44.1) | 0.009 |
| Children, n (%) | 665 (36.7) | 176 (39.5) | 189 (39.8) | 156 (37.0) | 144 (30.8) | 0.016 |
Tested by ANOVA for age and work hours per day, and by χ2 test for gender, administrative post, marriage and children.
BJSQ: Brief Job Stress Questionnaire.