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| Grade | Non-shrinking field group (N = 47) |
Shrinking field group (N = 50) |
P value |
|---|---|---|---|
| Grade 0 | 5 | 5 | |
| Grade 1 | 31 | 35 | |
| Grade 2 | 9 | 7 | |
| Grade 3 | 2 | 2 | |
| ≥ 2 Grade (%) | 11 (23.4) | 9 (18.0) | 0.51 |
