Table 2. Means and standard deviations of the birth weight and gestational age risk factors of the different stages of retinopathy of prematurity (ROP.

Risk factors	Without ROP (n = 61)	ROP I (n = 19)	ROP II (n = 14)	ROP III (n = 16)	P-value
Weight (grams)	1153.43 ± 241.48	1012.13 ± 183.70	1097.30 ± 213.43	814.35 ± 159.39	0.004
Gestational age (weeks)	30.24 ± 2.58	28.39 ± 2.77	27.96 ± 3.01	26.32 ± 1.69	< 0.001