What is the Methods information?

This information presents the details of the data sources and data analysis used to produce statistics about aging autistic individuals for our fact sheet series.

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METHODS

We used linked Medicaid and Medicare fee-for-service claims from 2019 via a data use agreement with the Centers for Medicare & Medicaid Services. We used the Medicaid Analytic eXtract (MAX) data files, the Transformed Medicaid Statistical Information System (T-MSIS) Analytic Files (TAF), and Medicare files containing data from all 50 states for information on enrollment, services, expenditures, and more.

We report statistics for those with autism spectrum disorder only, intellectual disability only, autism and intellectual disability combined, and neither disability. It is possible that individuals with no autism or intellectual disability could have another type of disability.

We analyzed claims for people ages 40 and older who were enrolled in Medicare and/or Medicaid for at least 10 months of a data year, as this reflected people who had consistent Medicaid coverage across that year. For Medicaid in particular, individuals may briefly disenroll due to administrative reasons (churning).

We identified people as having autism if they had at least one inpatient, or two other service claims, using a diagnosis code that indicated the person had autism (International Classification of Diseases, Ninth Edition [ICD-9-CM] and Tenth Edition [ICD-10-CM] codes beginning with 299). We included autistic people who also had other neurodevelopmental or psychiatric diagnoses.

We used percentages and means to convey how often and to what extent characteristics and experiences happened. We did not test for statistical significance. Estimates may differ slightly from estimates reported in other published scientific articles or reports due to differing analytic approaches to analyzing the data, including how missing data is handled and who is included or excluded from analysis.

Medicaid claims are an administrative data source, subject to billing and coding errors. MAX/TAF only includes Medicaid enrolled people, so it does not describe autistic people with private health insurance.

This fact sheet summarizes the characteristics of middle-aged and older autistic adults (age 40+) who use public health insurance (Medicaid, Medicare, or both). Claims data are helpful for understanding this population because many autistic adults rely on public insurance.

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This fact sheet series explores brain health in aging autistic adults, including cognitive changes and neurological well-being over time.

Fact sheets coming soon!

This fact sheet series highlights body health in aging autistic adults, focusing on physical health conditions, overall wellness, and access to healthcare.

Fact sheets coming soon!