Considerations for Analysis and Interpretation

• Intra-state eligibility policies - States have different eligibility criteria for each disability category. As a result, the proportion of students counted in each category will differ from state to state.

• Point-in-time count - The child count is a point-in-time count of students served. It is not a cumulative count of all students served throughout the school year. It is likely that States serve more students over the course of a school year than are served on December 1 (or the last Friday in November).

• State policy changes - Variations in a specific state's data from year to year may be the result of policy changes such as revisions to the states' eligibility criteria for particular disabilities.

• Data Notes - The data notes provided in each Annual Report to Congress help to explain year-to-year and State-to-State differences in the number of students served.

• Before 1992 - Prior to the introduction of the traumatic brain injury (TBI) and autism categories in 1990, IDEA served students with TBI and autism, but for reporting purposes they were reported in the Other Health Imparement category.