Table 1. Baseline characteristics of participants stratified by level of educational attainment (N = 1,275).
| Low educationa (n = 607) |
High educationa (n = 668) |
P for differenceb | |||
| N (%) | Mean (SD) | N (%) | Mean (SD) | ||
| Gender | <0.001 | ||||
| Male | 245 (40.4) | 401 (60.0) | |||
| Female | 362 (59.6) | 267 (40.0) | |||
| Age | 43.2 (10.6) | 40.0 (10.2) | <0.001 | ||
| 20–29 years old | 92 (15.2) | 139 (20.8) | |||
| 30–39 years old | 136 (22.4) | 210 (31.4) | |||
| 40–49 years old | 161 (26.5) | 168 (25.1) | |||
| 50–59 years old | 218 (35.9) | 151 (22.6) | |||
| Marital status | |||||
| Single | 322 (53.0) | 304 (45.5) | 0.007 | ||
| Married | 285 (47.0) | 364 (54.5) | |||
| Occupational type | <0.001 | ||||
| Managers | 26 (4.3) | 89 (13.3) | |||
| Nonmanual | 345 (56.8) | 458 (68.6) | |||
| Manual | 236 (38.9) | 121 (18.1) | |||
| Company size | <0.001 | ||||
| >1,000 employees | 144 (24.5) | 267 (41.1) | |||
| 300–999 | 91 (15.5) | 118 (18.2) | |||
| 50–299 | 167 (28.4) | 173 (26.6) | |||
| <50 | 186 (31.6) | 92 (14.2) | |||
SD: standard deviation.
aEducational attainment, measured on T2 or T3, was dichotomized into ≥16 years (high) or less (low).
bP value for difference was calculated by the chi square test for variables, except for age, for which the t test was used.