Participants’ characteristics with or without depressive symptoms: N (%)
| Characteristic | Total (n=1788) | Depressive symptoms | P value* | |
| Present (n=493) | Absent (n=1295) | |||
| Gender | ||||
| Male | 895 (50.1) | 245 (49.7) | 650 (50.2) | 0.851 |
| Female | 893 (49.9) | 248 (50.3) | 645 (49.8) | |
| Data missing | 0 | 0 | 0 | |
| Age (years) | ||||
| 18–29 | 156 (8.7) | 79 (16.0) | 77 (5.9) | <0.001 |
| 30–44 | 290 (16.2) | 139 (28.2) | 151 (11.7) | |
| 45–64 | 634 (35.5) | 177 (35.9) | 457 (35.3) | |
| 65–74 | 436 (24.4) | 52 (10.5) | 384 (29.7) | |
| ≧75 | 272 (15.2) | 46 (9.3) | 226 (17.5) | |
| Data missing | 0 | 0 | 0 | |
| Education level | ||||
| Less than high school | 81 (4.5) | 24 (4.9) | 57 (4.4) | 0.446 |
| High school | 555 (31.0) | 142 (28.8) | 413 (31.9) | |
| Junior college | 312 (17.4) | 99 (20.1) | 213 (16.5) | |
| More than or equal to college | 716 (40.1) | 212 (43.0) | 504 (38.9) | |
| Data missing | 124 | 16 | 108 | |
| Annual household income (million JPY) | ||||
| <3.00 (≒27 000 US dollar) | 493 (27.6) | 170 (34.5) | 323 (24.9) | 0.097 |
| 3.00–4.99 | 527 (29.5) | 114 (23.1) | 413 (31.9) | |
| 5.00–6.99 | 321 (18.0) | 91 (18.5) | 230 (17.8) | |
| 7.00–9.99 | 241 (13.5) | 71 (14.4) | 170 (13.1) | |
| ≧10.00 | 168 (9.4) | 41 (8.4) | 127 (9.8) | |
| Data missing | 38 | 6 | 32 | |
| Number of morbidities | ||||
| 1 | 815 (45.6) | 234 (47.5) | 581 (44.9) | 0.461 |
| 2 | 445 (24.9) | 116 (23.5) | 329 (25.4) | |
| ≧3 | 528 (29.5) | 143 (29.0) | 385 (29.7) | |
| Data missing | 0 | 0 | 0 | |
*P value by χ2 test for trend.