Clinical Study

A Prospective Study of the Incidence of Retinopathy of Prematurity in China: Evaluation of Different Screening Criteria

Table 3

The incidence rate of ROP with different zones according to gestational age and birth weight.

Non-ROP
(%)
Zone 1 ROP
(%)
Zone 2 ROP
(%)
Zone 3 ROP
(%)
AP-ROP
(%)
Total infants

GA, (W)
 ≤268 (66.7)2 (16.7)2 (16.7)0 (0)3 (25.0)12
 27-28100 (64.1)12 (7.7)34 (21.8)10 (6.4)8 (5.1)156
 29-30396 (76.9)14 (2.7)77 (15.0)28 (5.4)7 (1.4)515
 31-32904 (88.5)11 (1.1)58 (5.7)47 (4.6)1 (0.1)1021
 33-341139 (95.2)3 (0.3)28 (2.3)26 (2.2)0 (0)1196
 35-3694 (96.9)0 (0)2 (2.1)1 (1.0)0 (0)97

Total2641 (88.1)42 (1.4)201 (6.7)112 (3.7)19 (0.6)2997

BW, (g)
 ≤100038 (54.3)12 (17.1)18 (25.7)2 (2.9)8 (11.4)70
 1001–1250166 (66.9)12 (4.8)55 (22.2)15 (6.0)5 (2.0)248
 1251–1500409 (81.5)7 (1.4)58 (11.6)28 (5.6)2 (0.4)502
 1501–1750481 (86.8)7 (1.3)34 (6.1)31 (5.6)2 (0.4)554
 1751–2000668 (93.3)2 (0.3)23 (3.2)23 (3.2)2 (0.3)716
 >2000879 (96.9)2 (0.2)13 (1.4)13 (1.4)0 (0)907

Total2641 (88.1)42 (1.4)201 (6.7)112 (3.7)19 (0.6)2997