Variation in Rates of ADHD Diagnoses Across Public Schools in Arkansas.

Abstract

Objectives: This study characterized variation in rates of new medical diagnoses of ADHD among kindergartners and identified factors associated with diagnosis rates.

Methods: This study analyzed 87,383 kindergartners who were not diagnosed with ADHD prior to kindergarten who attended at least one of 490 elementary schools in Arkansas. The study examined five kindergarten cohorts from the 2015/16 to 2019/20 academic years, assessing school-level variation in ADHD diagnosis rates. Schools were categorized by quintiles of their ADHD diagnosis rates. A mixed-effects logistic regression model was used to examine individual-level factors associated with new ADHD diagnosis.

Results: Diagnosis rates varied 570% across school quintiles. Schools with higher rates of ADHD diagnoses served a higher percentage of African American children, children from lower-income families, and children living in neighborhoods with lower Child Opportunity Index (COI) scores. Results of an individual-level logistic regression analysis indicated children in census tracts with very high or high social and economic COI scores had lower odds of having new ADHD diagnoses compared to those from very low COI neighborhoods. Children who were young-for-grade had higher odds of an ADHD diagnosis. Children who were in schools providing universal free school meals had lower odds of an ADHD diagnosis, despite these schools serving more children from families with lower incomes, a finding that warrants further exploration.

Conclusions: New ADHD diagnoses in kindergarten varies substantially across schools.