Table 2

Outcomes at 21 months corrected age by GA

Entire cohort
n (%) (2340)
IQR (%) across sites*≤23 weeks
GA (63)
24 weeks
GA (186)
25 weeks GA (388)26 weeks GA (496)27 weeks GA (594)28 weeks GA (613)
Neurodevelopmental impairment*1071/2327 (46.0)37.9–50.639/62 (62.7)116/186 (62.4)202/387 (52.2)233/494 (47.2)260/587 (44.3)221/611 (36.2)
Significant neurodevelopmental impairment*384/2327 (16.5)11.2–23.023/62 (37.1)54/186 (29.0)80/387 (20.7)88/494 (17.8)88/587 (15.0)51/611 (8.4)
Cerebral palsy*146/2280 (6.4)3.1–8.68/61 (13.1)22/180 (12.2)32/382 (8.4)32/478 (6.7)23/574 (4.0)29/605 (4.8)
Bayley-III results
Motor
 Median (IQR)94 (85, 100)91–9785 (73, 94)88 (79, 97)91 (82, 100)94 (85, 100)94 (88, 103)97 (88, 103)
 Score <85*452/2078 (21.8)16.0–28.623/50 (46.0)57/168 (33.9)94/352 (26.7)106/441 (24.0)82/517 (15.9)90/550 (16.4)
 Score <70*140/2078 (6.7)4.8–15.89/50 (18.0)21/168 (12.5)31/352 (8.8)34/44 (7.7)23/517 (4.5)22/550 (4.0)
Cognitive
 Median (IQR)95 (90, 105)95–10088 (80, 95)90 (80, 100)95 (85, 105)95 (85, 105)95 (90, 105)100 (90, 105)
 Score <85*318/2168 (14.7)11.8–20.419/52 (36.5)44/172 (25.6)63/364 (17.3)78/458 (17.0)74/552 (13.4)40/570 (7.0)
 Score <70*72/2168 (3.3)2.8–7.94/52 (7.7)10/172 (5.8)22/364 (6.0)16/458 (3.5)12/552 (2.2)8/570 (1.4)
Language
 Median (IQR)91 (79, 100)88–9483 (68, 94)84 (74, 97)89 (77, 100)91 (79, 100)91 (79, 103)94 (83, 103)
 Score <85*739/2094 (35.3)24.9–43.327/50 (54.0)85/169 (50.3)141/359 (39.3)158/447 (35.4)190/528 (36.0)138/541 (25.5)
 Score <70*228/2094 (10.9)7.4–16.414/50 (28.0)32/169 (18.9)52/359 (14.5)51/447 (11.4)54/528 (10.2)25/541 (4.6)
Hearing
 Any hearing impairment*180/2204 (8.2)2.5–13.39/61 (14.8)19/177 (10.7)43/371 (11.6)30/457 (6.6)37/562 (6.6)42/574 (7.3)
 Hearing aid or cochlear implant*58/2249 (2.6)0–3.16/62 (9.7)9/182 (5.0)17/372 (4.6)9/468 (1.9)10/574 (1.7)7/591 (1.2)
Vision
 Unilateral or bilateral visual impairment*41/2138 (1.9)0–3.78/55 (14.6)6/170 (3.5)11/360 (3.1)7/448 (1.6)6/542 (1.1)<5
 Bilateral visual impairment35/2138 (1.6)0–3.17/55 (12.7)6/70 (3.5)10/360 (2.8)5/448 (1.1)5/542 (0.9)<5
  • *Cochran-Armitage trend test for GA p<0.01.

  • Bayley-III, Bayley Scales of Infant and Toddler Development-Third Edition; GA, gestational age.