| Birth weights, grams | Newborns without ROP | Newborns with ROP |
| Unspecified | 2.19 (SD5.3) | 67.9 (SD 79.1) |
| <500 | 6.89 (SD 58.7) | 101.72 (SD 85.6) |
| 500–749 | 37.01 (SD 109.4) | 96.35 (SD 65.3) |
| 750–999 | 46.64 (SD 89.8) | 74.34 (SD 55.0) |
| 1000–1249 | 37.06 (SD 60.6) | 56.44 (SD 40.6) |
| 1250–1499 | 27.90 (SD 43.6) | 44.90 (SD 32.9) |
| 1500–1749 | 19.73 (SD 31.8) | 37.09 (SD 36.6) |
| 1750–1999 | 12.64 (SD 24.9) | 28.9 (SD 41.3) |
| 2000–2499 | 5.99 (SD 16.6) | 30.08 (SD 50.9) |
| >2500 | 3.93 (SD 11.7) | 29.04 (SD 67.1) |
LOS, length of stay; ROP, retinopathy of prematurity.