. Author manuscript; available in PMC: 2014 Mar 1.

Published in final edited form as: Res Dev Disabil. 2013 Jan 8;34(3):1059–1068. doi: 10.1016/j.ridd.2012.12.002

Table 1.

Demographics by Developmental Status at Time of Enrollment (n=245).

	Typical Development (n = 129)	Developmental Delay (n = 116)	DD vs. TD difference

Child variables:
Gender (% girls)	47.7	33.3	χ² = 5.04^*
Race (% White)	60.5	56.9	χ² = 0.32
Mean (SD) BSID, age 3	104.1 (12.2)	60.3 (13.0)	t = 25.95^***
Mean (SD) Stanford Binet IQ, age 5	104.0 (12.0)	65.7 (19.0)	t =18.32^***
Family variables:
% with siblings at age 5	72.1	69.8	χ² = 0.14
Mother age at child age 5, M (SD)	36.1 (5.6)	35.0 (6.3)	t = 1.42
Mother education (% college degree)	61.2	31.0	χ² = 22.38^***
Father education (% college degree)	62.0	37.9	χ² = 14.17^***
Maternal employment (% employed)	64.8	47.7	χ² = 4.71^*
Marital status (% married)	89.1	80.2	χ² = 3.84^†
Family income (% earning $50,000+)	62.1	37.9	χ² = 8.98^**

^†

p < 0.10,

p < 0.05,

^**

p < 0.01,

^***

p < 0.001