Table 2. Frequencies of Eventsa.
| Characteristic | Patients in the Full Cohort,b No. (%) (N = 290 992) |
Patients in the P-VLBW Subcohort, No. (%) (N = 2015) |
|---|---|---|
| All ROP | 579 (0.20) | 548 (32.16) |
| Severe ROP | 148 (0.05) | 147 (8.63) |
| All ROP or death before the first ROP examination | 868 (0.30) | 800 (40.90) |
| Severe ROP or death before the first ROP examination | 437 (0.15) | 399 (20.40) |
| Death before discharge | 565 (0.19) | 297 (15.18) |
Abbreviations: NICU, neonatal intensive care unit; P-VLBW, preterm very low-birth-weight; ROP, retinopathy of prematurity.
a
Ninety-nine patients were excluded from both cohorts because they transferred from the NICU before receiving the initial ROP examination.
b
Two hundred eighty-nine additional patients in the full cohort who died before their first ROP examination were excluded from the analysis of ROP outcomes, which did not incorporate death. These patients were included in the analyses for composite outcomes, which included death.