Table 2: Comparison of OHI-S scores, caries treatment needs, and overall knowledge scores within caries subgroups of III- and V-grade children in all three schools
| III-grade median (range) | V-grade median (range) | ||||||||||||||||
| Schools | Subgroup a | Subgroup b | Subgroup c | pa-value | Subgroup a | Subgroup b | Subgroup c | pa-value | |||||||||
| OHI-S scores | |||||||||||||||||
| School I | 0.83 (0.83) | 1.00 (0.92) | 0.83 (0.66) | 0.54 | 0.50 (0.58) | 0.99 (1.26) | 0.50 (0.84) | 0.28 | |||||||||
| School II | 1.00 (0.5) | 1.00 (0.71) | 1.00 (0.37) | 0.26 | 1.00 (1) | 1.00 (0.66) | 1.00 (0.33) | 0.24 | |||||||||
| School III | 0.33 (0.83) | 0.33 (0.5) | 0.83 (0.66) | 0.001 | 1.16 (1) | 1.00 (0.83) | 1.00 (0.96) | 0.29 | |||||||||
| Caries treatment needs score | |||||||||||||||||
| School I | 0 (0) | 1.00 (2) | 6.00 (3) | <0.001 | 0 (0) | 1.50 (2) | 5.00 (4) | <0.001 | |||||||||
| School II | 0 (0) | 3.00 (2) | 7.00 (4) | <0.001 | 0 (0) | 2.00 (2) | 4.00 (2) | <0.001 | |||||||||
| School III | 0 (0) | 3.00 (1) | 5.00 (3) | <0.001 | 0 (1) | 2.00 (3) | 6.00 (5) | <0.001 | |||||||||
| Overall knowledge score | |||||||||||||||||
| School I | 5.00 (2) | 5.50 (3) | 5.00 (2.75) | 0.710 | 6.00 (2.5) | 5.50 (2.25) | 6.00 (1) | 0.540 | |||||||||
| School II | 5.00 (1) | 6.00 (2) | 5.00 (2.25) | 0.81 | 6.00 (2) | 6.00 (2) | 6.00 (2) | 0.52 | |||||||||
| School III | 5.00 (2) | 6.00 (2) | 5.00 (0.75) | 0.16 | 6.00 (3) | 6.00 (2) | 5.00 (3) | 0.320 | |||||||||
aChi-square test