Regions | Range of | ||||
1 to 5 years | 6 to 10 years old | 11 to 15 years old | 16 to 20 years old | More than 20 years | |
Dosso | 61 | 18 | 1 | 7 | 1 |
Maradi | 67 | 20 | 4 | 5 | 0 |
Tahoua | 44 | 28 | 3 | 5 | 6 |
Zinder | 69 | 23 | 2 | 3 | 1 |
Average | 60 ± 0.1 | 22 ± 0.04 | 3 ± 0.01 | 5 ± 0.02 | 3 ± 0.03 |
Chi-square | * | ns | ns | ns | ** |