| Grades | Baseline No (%) | 3 months No (%) | 9 months No (%) |
| G0 | 63 (100) | 58 (92.1) | 60 (95.2) |
| G1 | 0 | 2 (3.2) | 2 (3.2) |
| G2 | 0 | 2 (3.2) | 1 (1.6) |
| G3 | 0 | 1 (1.6) | 0 |