Table 1.
Community characteristics in intervention and control groups at the time of enrollment
| Control group | Intervention group | P-valuea | |
|---|---|---|---|
| Distribution among 30 communities | |||
| Number of communities | 15 | 15 | |
| Population size: number (%) | |||
| ≤450 people | 9/15 (60%) | 9/15 (60%) | 1.00 |
| >450 people | 6/15 (40%) | 6/15 (40%) | |
| Distance to nearest hospital: number (%) | |||
| <250km | 2/15 (13%) | 4/15 (27%) | 0.65 |
| ≥250 km | 13/15 (87%) | 11/15 (73%) | |
| Fluoride concentration in drinking water: number (%) | |||
| <0.6 ppm F | 10/15 (67%) | 12/15 (80%) | 0.68 |
| ≥0.6 ppm F | 5/15 (33%) | 3/15 (20%) | |
| Distribution among 666 children | |||
| Number of children | 322 | 344 | |
| Population size: number (%) | |||
| ≤450 people | 155/322 (48%) | 104/344 (30%) | <0.01 |
| >450 people | 167/322 (52%) | 240/344 (70%) | |
| Distance to nearest hospital: number (%) | |||
| <250 km | 28/322 (9%) | 46/344 (13%) | 0.06 |
| ≥250 km | 294/322 (91%) | 298/344 (87%) | |
| Fluoride concentration in drinking water: number (%) | |||
| <0.6 ppm F | 262/322 (81%) | 315/344 (92%) | <0.01 |
| ≥0.6 ppm F | 60/322 (19%) | 29/344 (8%) | |
a
P-values test null hypothesis of equivalence between control and intervention using Fisher's exact test.