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Data distribution before and after data cleaning
| Characteristic | Before cleaning | After cleaning |
|---|---|---|
| Number of image groups | 6146 | 6074 |
| Severe myopia (SE < -6 D) | 1708 | 1699 |
| Moderate myopia (−6 D ≤ SE < -3 D) | 2395 | 2378 |
| Mild myopia (−3 D ≤ SE < 0 D) | 1919 | 1879 |
| Emmetropia and hyperopia (SE ≥ 0 D) | 124 | 118 |
