Table 1.

online. Characteristics of children who were eligible for follow up (had some or all follow-up tests/examinations at 2 years) and were seen at 10 years and those eligible for follow up but not seen at 10 years. These are column percents.

		Eligible at 10 years*		Row N
		Seen**	Not seen
Maternal characteristics
Racial identity	White	64	50	714
	Black	26	31	322
	Other	11	19	151
Hispanic	Yes	10	19	147
Age, years	< 21	13	19	170
	21-35	67	66	802
	> 35	20	16	226
Education, years	≤ 12	41	52	506
	> 12, < 16	23	24	270
	≥ 16	36	24	376
Single marital status	Yes	39	52	513
Public insurance	Yes	35	52	464
Smoking during pregnancy	Yes	14	16	162
Passive smoking	Yes	24	28	293
Pre-pregnancy BMI	< 18.5	8	8	90
	18.5, < 30	69	74	809
	≥ 30	23	18	248
Gestational diabetes	Yes	7	8	82
Perinatal characteristics
Any antenatal steroid	Yes	89	82	1073
Histologic chorioamnionitis¶	Yes	32	39	411
	Missing	8	9	99
Delivery complication	Preterm labor	46	41	534
	Preterm PROM	22	22	363
	Preeclampsia	13	13	153
	Abruption	10	11	128
	Cervical Insufficiency	5	8	72
	Fetal indication	4	4	49
Cesarean delivery	Yes	66	67	795
Multifetal pregnancy	Yes	35	27	393
Newborn characteristics
Sex	Male	51	54	621
Gestational age, weeks	23-24	21	20	245
	25-26	46	48	553
	27	34	32	400
Birth weight, grams	≤ 750	37	35	436
	751-1000	43	44	520
	> 1000	20	21	242
Birth weight Z-score†	< −2	6	3	62
	≥ −2, < −1	13	13	153
	≥ −1	81	85	983
Head circumference Z-score†	< −2	8	6	89
	≥ −2, < −1	21	25	260
	≥ −1	70	69	806
Postnatal Characteristics
Growth velocity quartile††	Lowest	23	29	290
	Highest	25	24	291
Bacteremia, week 1	Yes	10	10	76
Bacteremia, weeks 2-4	Yes	30	28	296
Necrotizing enterocolitis‡	Yes	8	6	88
Chronic lung disease‡‡	Yes	52	46	598
BSID-II MDI < 70 at 2 years	Yes	26	29	268
Cerebral palsy at 2 years	Yes	10	14	119
Corrected age at 2 years	< 24 months	25	28	276
Maximum column N		871	327	1198

^*Eligible at 10 years are the 1198 children who survived to 10-years

^**Seen at 10 years are the 871 children for whom a BMI centile could be calculated (weight and height were collected).

^¶Grades 3 and 4

^†Yudkin standard

^††1000 × [(weight day 28 - weight day 7)/weight day 7]/21

^‡Stage IIIa, IIIb, or perforation

^‡‡Receiving O₂ at 36 weeks PCA