Table 2 Prevalence ratios (PRs) and 95% confidence intervals (CIs) for decayed and/or filled teeth in relation to study variables
From: Household smoking and dental caries in schoolchildren: the Ryukyus Child Health Study
| Â | Prevalence (%) | Crude PR (95% CI) |
|---|---|---|
Sex | Â | Â |
   Female | 8624/10502 (82.1) | 1.00 |
   Male | 8348/10201 (81.8) | 1.00 (0.98-1.01) |
Age (y) | Â | Â |
   6-8 | 4989/6088 (81.5) | 1.00 |
   9-11 | 6301/7522 (83.8) | 1.03 (1.01-1.04) |
   12-15 | 5712/7093 (80.5) | 0.99 (0.97-1.01) |
Region of residence | Â | Â |
   Nago city | 3014/3540 (85.1) | 1.00 |
   Naha city | 13958/17163 (81.3) | 0.96 (0.94-0.97) |
Toothbrushing frequency (times/day) | Â | Â |
   <1 | 1372/1566 (87.6) | 1.00 |
   1 | 3823/4518 (84.6) | 0.97 (0.94-0.99) |
   2 | 9688/11925 (81.2) | 0.93 (0.91-0.95) |
   ≥3 | 2089/2694 (77.5) | 0.89 (0.86-0.91) |
Use of fluoride | Â | Â |
   No | 3705/4531 (81.8) | 1.00 |
   Yes | 13267/16172 (82.0) | 1.00 (0.99-1.02) |
Paternal educational level | Â | Â |
   Junior high school | 1357/1540 (88.1) | 1.00 |
   High school | 7740/9160 (84.5) | 0.96 (0.94-0.98) |
   Junior college or vocational technical school | 2518/3097 (81.3) | 0.92 (0.90-0.95) |
   University | 5357/6906 (77.6) | 0.88 (0.86-0.90) |
Maternal educational level | Â | Â |
   Junior high school | 900/1024 (88.0) | 1.00 |
   High school | 7654/9071 (84.4) | 0.96 (0.94-0.98) |
   Junior college or vocational technical school | 6948/8704 (79.3) | 0.91 (0.89-0.93) |
   University | 1473/1904 (77.4) | 0.88 (0.85-0.91) |
Daily sugar intake (g/1,000 kcal) | Â | Â |
   <3.0200 | 4054/5176 (78.3) | 1.00 |
   3.0200-4.6510 | 4192/5176 (81.0) | 1.03 (1.01-1.05) |
   4.6511-6.8298 | 4335/5176 (83.8) | 1.07 (1.05-1.09) |
   ≥6.8299 | 4391/5175 (84.9) | 1.08 (1.06-1.10) |