Table I.

Descriptive characteristics of children with intellectual and developmental disabilities and medical claims paid by Medicaid in 4 US states

Categories	n	% of Sample
Age (y)
<1	1825	1.7
1-2	10 137	9.3
3-6	29 947	27.5
7-12	40 220	37.0
13-17	26 660	24.5
Sex
Male	75 417	69.3
Female	33 371	30.7
Race
White	40 269	37.0
Black	20 665	19.0
Hispanic	20 638	19.0
Other	5929	5.4
Unknown	21 288	19.6
Intellectual and developmental disability condition (using group hierarchy)
Down syndrome/trisomy/autosomal deletions	8099	7.4
Other genetic causes	2045	1.9
Fetal alcohol syndrome	964	0.9
Cerebral palsy	12 301	11.3
Autism spectrum disorders	51 121	47.0
Intellectual disability (all levels)	34 259	31.5