Table 1

Demographic characteristics of birthweight groups

Birthweight group
500–999 g1000–1500 g>2499 g
No. survived 8612460
No. lost (% survivors)3  (3%)5  (4%)4  (7%)
No. refused (% survivors)4 (5%)13 (10%)12 (20%)
No. inaccessible (% survivors)1 (1%)4 (3%)2 (3%)
No. seen at age 14 (% survivors)78 (91%)102 (82%)42 (70%)
Gestational age (wk); mean (SD)27.5 (2.3)29.6 (1.5)39.9 (1.0)1-150
Birth weight (g); mean (SD)859 (100)1259 (145)3420 (427)1-150
Birthweight SD score; mean (SD)−1.04 (1.24)−0.48 (0.84)−0.14 (0.79)1-150
No. with birth weight ⩽2 SD (% seen)14 (18%)7 (7%)0 (0%)1-150
No. received antenatal steroids (% seen)39 (50%)52 (51%)0 (0%)
No. males (% seen)35 (45%)55 (54%)26 (62%)
No. with BPD (% seen)33 (42%)9 (9%)0 (0%)
Age seen (y); mean (SD)14.1 (0.2)14.2 (0.3)14.2 (0.1)
Height at 14 years of age (cm); mean (SD)158.2 (8.4)160.7 (7.8)164.3 (8.2)1-150
Height at 14 years of age—Z score; mean (SD)−0.43 (1.09)−0.11 (1.05)0.26 (1.07)1-150
No. exposed to smoking (% seen)38 (49%)55 (54%)16 (38%)
No. active smokers (% seen)2 (2%)8 (8%)3 (7%)
No. with asthma at 14 (% seen)12 (15%)21 (21%)9 (21%)
No. with mother born in English speaking country (% seen) 59 (76%)82 (80%)27 (64%)
No. of lower social class (% seen)38 (49%)28 (27%)13 (31%)1-150
No. with maternal schooling >10 years (% seen)29 (37%)39 (38%)21 (50%)
  • 1-150 Statistically significant difference between groups.