Table 1.

Maternal and pregnancy characteristics that are correlates of inclusion or exclusion at each stage of the study. These are column percents.

Maternal and pregnancy characteristics		Sample
		Cranial ultrasound		Survived to 24 months		Evaluated at 24 months
		Yes	No	Yes	No	Yes	No
Racial identity	White	58	69	60	50	61	50
	Black	29	22	27	37	27	34
	Other	13	10	13	13	12	16
Maternal age	< 21	14	16	14	16	13	28
	21-35	68	67	67	71	67	61
	> 35	18	16	19	14	20	10
Years of education	< 12	17	15	17	21	16	27
	12 (High School)	28	27	27	31	27	26
	>12 to <16	24	27	23	28	23	27
	16 (College)	18	21	18	13	19	16
	> 16	13	9	14	6	15	3
Married	Yes	56	69	57	50	59	39
Public insurance	Yes	42	34	40	52	39	51
Primagravida	Yes	40	40	41	35	41	45
Conception assistance	Yes	20	34	21	13	22	15
Antenatal steroids	Complete	62	61	64	56	64	58
	Partial	27	25	26	29	25	34
	None	11	14	10	14	10	8
Pregnancy complication	PTL	44	45	45	42	45	38
	pPROM	21	39	22	18	22	23
	PE	14	0	13	17	13	9
	Abruption	10	2	11	9	11	10
	Cerv Insuffiency	6	6	6	6	5	15
	Fetal Indication	5	8	4	8	4	5
Cesarean delivery	Yes	65	63	66	58	67	61
Maximum number of infants		1455	51	1198	257	1102	96
Total		1506		1455		1198