Table 1.

Descriptive Characteristics of Adults With Intellectual and Developmental Disabilities Insured by Medicaid in 2012 in 4 US States^a

	n	Percentage of Sample
Age at enrollment, y
18–24	33122	45.6
25–34	19037	26.2
35–44	8893	12.3
45–54	6917	9.5
55–64	4626	6.4
Gender
Male	41787	57.6
Female	30808	42.4
Intellectual and developmental disabilities condition (using group hierarchy)
Down syndrome/trisomy/autosomal deletions	5386	7.4
Other genetic causes	1737	2.4
Fetal alcohol syndrome	369	0.5
Cerebral palsy	13 533	18.6
Autism spectrum disorders	17 284	23.8
Intellectual disability (all levels)	34 286	47.2
Total	72 595	100

^aThe 4 states included are Iowa, Massachusetts, New York, and South Carolina.