Table 1.
Distribution of selected characteristics in 20,703 schoolchildren, RYUCHS, Japan
| Variable | n (%) |
|---|---|
| Male sex | 10,201 (49.3) |
| Age (y) | |
| 6-8 | 6,088 (29.4) |
| 9-11 | 7,522 (36.3) |
| 12-15 | 7,092 (34.3) |
| Region of residence | |
| Nago city | 3,540 (17.1) |
| Naha city | 17,163 (82.9) |
| Toothbrushing frequency (times/day) | |
| <1 | 1,566 (7.6) |
| 1 | 4,518 (21.8) |
| 2 | 11,925 (57.6) |
| ≥3 | 2,694 (13.0) |
| Use of fluoride | |
| No | 4,531 (21.9) |
| Yes | 16,172 (78.1) |
| Paternal educational level | |
| Junior high school | 1,540 (7.4) |
| High school | 9,160 (44.2) |
| Junior college or vocational technical school | 3,097 (15.0) |
| University | 6,906 (33.4) |
| Maternal educational level | |
| Junior high school | 1,024 (5.0) |
| High school | 9,071 (43.8) |
| Junior college or vocational technical school | 8,704 (42.0) |
| University | 1,904 (9.2) |
| Daily sugar intake (g/1,000 kcal) | |
| <3.0200 | 5,176 (25.0) |
| 3.0200-4.6510 | 5,176 (25.0) |
| 4.6511-6.8298 | 5,176 (25.0) |
| ≥6.8299 | 5,175 (25.0) |