Findings from 2018 data
How many 8-year-old children were identified with ASD in Minnesota?
Using data from 2018, MN-ADDM researchers found 1 in 36 (2.8%) 8-year-old children were identified with ASD. This is higher than the overall ADDM Network prevalence of 8-year-old children identified with ASD (1 in 44 or 2.3%) in the United States where the CDC tracked ASD in 2018.
When were children first diagnosed with ASD in Minnesota?
What was the percentage of children with ID in Minnesota?
Which children were more likely to be identified with ASD in Minnesota?
Prevalence per 1,000 children
95% confidence interval per 1,000
1 in 36
1 in 23
1 in 100
Asian or Pacific Islander
1 in 47
Black, Non-Hispanic, Non-Somali
1 in 30
1 in 29
1 in 55
1 in 40
201 American Indian or Alaska Native children were included in the denominator but were not included in prevalence estimations due to low numbers of children with ASD.
API: Asian/Pacific Islander
291 Hmong children were included in the non-Hispanic API group but were not analyzed separately due to low case numbers.
* p<.05, Black, non-Somali and Black, Somali children had a higher ASD prevalence than Hispanic children.
**p<.001, Males had a higher ASD prevalence than females.
What do the sex and race/ethnicity differences in prevalence rates tell us?
Males aged 8 years had a higher ASD prevalence than females aged 8 using a p-value of <.001.
Black-non-Somali and Black-Somali 8-year-old children had a higher ASD prevalence than Hispanic 8-year-old children using a p-value of <.05.
How common is intellectual disability for children who have ASD?
Among children identified with ASD who had IQ information available, 29% also had intellectual disability.
- Intelligence quotient (IQ) scores were available for 81% of children identified with ASD by MN-ADDM. Intellectual disability is defined as IQ score ≤ 70.
This information is based on the analysis of data collected from the health and educational records of children who were 4 and 8 years old in 2018. In addition to the race/ethnicity categories routinely studied by CDC, in MN we are interested in understanding prevalence for children in our Hmong and Somali communities.
The tracking area included parts of three counties (Anoka, Hennepin, Ramsey) including the large metropolitan city of Minneapolis.
8-year-old children in the tracking area included 10,081 children of the following race and ethnicity
- American Indian or Alaska Native - 2%
- Asian or Pacific Islander – 8%
- Black, non-Somali, non-Hispanic – 20%
- Black, Somali - 5%
- Hispanic –14%
Limitations and Implications
This is the third time Minnesota data has been included in findings from the ADDM Network. The findings in this report reflect a small number of children concentrated in a large metropolitan area. The higher prevalence estimate in Minnesota, compared to ADDM-wide estimates, is not unanticipated for a large metropolitan area.
In Minnesota, there are differences between the proportions of boys and girls identified with ASD, with more boys than girls. This is consistent with previous estimates. (Note: the ADDM project only collects data on males and females and does not include sexual orientation or gender identification information.)
In Minnesota, we identify ASD much later than when first concerns are reported. The median age of the first ASD diagnosis for 8-year-olds was 5 years and 3 months, which was the latest age across the ADDM Network. This lag is concerning due to the critical importance of early identification and intervention. Many states, including MN have invested in early intervention to help children and families gain access to early intervention services. For example, Minnesota’s Early Intensive Developmental and Behavioral Intervention (EIDBI) Benefit provides early intensive intervention for people with ASD and related conditions. To learn more about the EIDBI benefit follow this link:
We found varying prevalence rates across racial and ethnic groups in Minnesota. The small number of children in some of these groups makes it difficult to determine whether the rates of children with ASD truly are different across groups. Additionally, the confidence intervals around the prevalence estimates are large (e.g., 13.6-33.7 for Asian/Pacific Islander children), and this tells us we should use caution before drawing conclusions about any differences between groups. As the geographic area for MN-ADDM continues to grow and include more children, we will be better able to judge whether there are true differences in prevalence estimates. If differences are found, it will be important to focus on general health disparities that may influence these differences.