TABLE 1.

Demographic Characteristics of Infants With DP and Control Infants Without DP

Characteristic	n (%)
	Case (N = 235)	Control (N = 237)
Gender
Male	153 (65)	140 (59)
Female	82 (35)	97 (41)
Age
4–5 mo	66 (28)	99 (42)
6–7 mo	107 (45)	78 (33)
8–9 mo	46 (20)	52 (22)
10–12 mo	16 (7)	8 (2)
Race/ethnicity
White	159 (68)	145 (61)
Asian/Pacific   Islander	14 (6)	13 (5)
Black	0 (0)	6 (3)
Hispanic	28 (12)	30 (13)
Mixed race/other	34 (14)	43 (18)
Familial SES
I (high)	82 (35)	63 (27)
II	88 (37)	100 (42)
III	40 (17)	47 (20)
IV	16 (7)	21 (9)
V (low)	9 (4)	6 (3)