The overall ASD prevalence was 16.8 per 1,000 (1 in 59) children. In 2000, the rate was estimated at 6.7 per 1,000. (The researchers caution that the states included in the monitoring network have changed over time.)
New Jersey had the highest prevalence of ASD (29.3 per 1,000, or 2.93%), and the difference when compared with each of the other 10 states was statistically significant (P less than .01).
The overall ASD rate was 26.6 per 1,000 for boys and 6.6 per 1,000 for girls (P less than .01). For whites, it was 17.2 per 1,000, while blacks (16.0 per 1,000) and Hispanics (14.0 per 1,000) had lower rates.
When intelligence quotient information was available, 44% of those with ASD had IQ greater than 85. Blacks (44%) and Hispanics (35%) with ASD were more likely than whites (22%) to have IQs less than or equal to 70, a sign of intellectual disability, the researcher reported.