Table 2. Demographic Characteristics of Case and Control Siblings by Cohort.

Characteristics	Siblings, No. (%)		P value
	Case cohort	Control cohort
Prematurity cohort
Siblings, No.	784	2807	NA
Age, y
0 to <3	30 (3.8)	73 (2.6)	<.001
3 to <5	164 (20.9)	887 (31.6)
≥5	590 (75.3)	1847 (65.8)
Sex
Female	373 (47.6)	1383 (49.3)	.40
Male	411 (52.4)	1424 (50.7)
Race and ethnicity
Asian	24 (3.1)	131 (4.7)	<.001
Black	88 (11.2)	167 (6.0)
Hispanic	93 (11.9)	281 (10.0)
White	456 (58.2)	1845 (65.7)
Missing or other	123 (15.7)	383 (13.6)
Cardiac cohort
Siblings, No.	770	2292	NA
Age, y
<19	25 (3.3)	51 (2.2)	<.001
19 to <29	207 (26.9)	776 (33.9)
≥29	538 (69.9)	1465 (63.9)
Sex
Female	413 (53.6)	1135 (49.5)	.048
Male	357 (46.4)	1157 (50.5)
Race and ethnicity
Asian	30 (3.9)	95 (4.1)	.18
Black	72 (9.4)	153 (6.7)
Hispanic	76 (9.9)	226 (9.9)
White	496 (64.4)	1536 (67.0)
Missing or other	96 (12.5)	282 (12.3)
Oncologic cohort
Siblings, No.	2072	4058	NA
Age, y
0 to <3	75 (3.6)	35 (0.9)	<.001
3 to <5	98 (4.7)	147 (3.6)
≥5	1899 (91.7)	3876 (95.5)
Sex
Female	1020 (49.2)	1915 (47.2)	.13
Male	1052 (50.8)	2143 (52.8)
Race and ethnicity
Asian	64 (3.1)	163 (4.0)	.30
Black	103 (5.0)	219 (5.4)
Hispanic	231 (11.2)	413 (10.2)
White	1467 (70.8)	2860 (9.9)
Missing or other	207 (10.0)	403 (9.9)
Neurologic cohort
Siblings, No.	4292	8885	NA
Age, y
0 to <3	171 (4.0)	117 (1.3)	<.001
3 to <5	293 (6.8)	408 (4.6)
≥5	3828 (89.2)	8360 (94.1)
Sex
Female	2145 (50.0)	4330 (48.7)	.18
Male	2147 (50.0)	4555 (51.3)
Race and ethnicity
Asian	136 (3.2)	436 (4.9)	<.001
Black	265 (6.2)	590 (6.6)
Hispanic	477 (11.1)	922 (10.4)
White	3024 (70.5)	6150 (69.2)
Missing or other	390 (9.1)	787 (8.9)

Abbreviation: NA, not applicable.