Time | Number of cases | Healthy | Sick | Qualification |
Months | 196 | 156 (79.6%) | 40 (20.4%) | 7. 47 ± 2.24 |
1 year | 132 | 110 (83.3%) | 22 (16.7%) | 7. 84 ± 2.34 |
2 to 5 years | 382 | 325 (85.1%) | 57 (14.9%) | 8.08 ± 2.09 |
6 to 9 years | 156 | 147 (94.2%) | 9 (5.8%) | 8.54 ± 1.82 |
10 years or more | 186 | 175 (94.1%) | 11 (5.9%) | 8.67 ± 1.69 |