Limitations and Implications
Implications
This is the fifth time Minnesota data has been included in findings from the ADDM Network. The 2022 overall 8-year-old prevalence rate of 1 in 28 is higher than the 2020 prevalence rate of 1 in 34. Autism prevalence increased between 2020 and 2022 for females and for Asian/Pacific Islander, Black, and Multiracial children. However, the portions of Ramsey and Hennepin counties included in prevalence estimates differed in 2020 and 2022, which may have impacted prevalence.
In Minnesota, and across the ADDM network, we saw a decrease in the male-to-female ratio of autism prevalence. In the past, males typically had an autism rate 4 times higher than females. In 2022, the male-to-female ratio was 3.1 in Minnesota and 3.4 across ADDM sites combined. (Note: the ADDM project only collects data on male and female sex as indicated in records and does not include gender identification information.) In terms of race/ethnicity, as in 2020, we saw higher rates of autism for Hispanic children compared to White. We also saw a higher autism rate for Black and Multiracial children compared to White in 2022; these three groups had similar autism rates in 2020.
In Minnesota, we identify autism much later than when first concerns are reported. The median age of the first autism diagnosis for 8-year-olds was 4 years and 7 months. 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 autism and related conditions. To learn more about the EIDBI benefit, follow this link:
Minnesota experienced marked reductions in autism evaluations and identifications with the onset of the COVID-19 pandemic in March 2020. These reductions persisted through the end of 2020 in Minnesota, recovered for periods of 2021, and declined again in 2022.
Other states in the ADDM network showed varying patterns in the number of evaluations and identifications of autism post-pandemic [insert link to MMWR when available]."
Limitations
The findings in this report reflect a small number of children concentrated in a large metropolitan area and may not reflect prevalence across the entire state.
The numbers of 8-year-old children with autism from some racial/ethnic groups are small, and their prevalence estimates will be less precise than estimates for larger-sized populations. Confidence intervals show the range in which we are 95% confident that true prevalence lies, and a larger confidence interval means less precision (e.g., 39.3–59.8 for Multiracial children). This tells us we should use caution before drawing conclusions about differences between some groups.
MN-ADDM reviewed records from participating public school special education programs but did not review private school education records or all charter school education records in our geographic area. Similarly, if a child was identified with autism in a clinic outside of those included in MN-ADDM’s geographic area, their health records may not have been captured. Incomplete information could lead to misclassifying children’s cognitive ability, overestimating the age when they were first evaluated or when autism was identified, or failing to capture that the children were identified as having autism.