Importance Early identification and treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms in preschool-age children is important for mitigating social-emotional and academic problems. Clinical practice guidelines recommend first-line behavior intervention before considering medication treatment for children 4-5-years-old.

Objective To assess variation in rates of ADHD identification and rates and timing of medication treatment in children 3-5-years-old in primary care settings across eight US pediatric health systems and to identify patient factors associated with the time from diagnosis to prescription.

Design Retrospective cohort study of electronic health records.

Setting Primary care clinics affiliated with eight academic institutions participating in the PEDSnet Clinical Research Network.

Participants Children 3-5-years-old seen in primary care between 2016-2023.

Exposure ADHD diagnosis at age 4-5 years.

Main Outcomes and Measures Outcomes: (1) rate of ADHD diagnosis; (2) rate of stimulant and non-stimulant prescription after diagnosis before age 7, (3) time from first ADHD-related diagnosis (including symptom-level diagnoses) to medication prescription. Independent variables: institution, year of diagnosis, patient age, sex, race/ethnicity, medical insurance, and presence of comorbidities.

Results Of 712,478 children seen in primary care at ages 3-5 years, 9,708 (1.4%) received an ADHD diagnosis at age 4-5 years (range 0.5-3.1% across institutions). Of those with ADHD, 76.4% (n=7414) were male, 39.0% (n=3782) were White. Of 9,708 preschool-age children with ADHD, 68.2% (6624) were prescribed ADHD medications before age 7, 42.2% (n=4092) were prescribed medications within 30 days of the first documentation of an ADHD-related diagnosis (range 26.0-49.0% across institution). Asian (aHR 0.50, CI 0.38-0.65), Hispanic (aHR 0.75, CI 0.70-0.81), and Black (aHR 0.90, CI 0.85-0.96) children with ADHD were less likely to be prescribed medication early compared to White children. Older (aHR 1.64, CI 1.57-1.72), male (aHR 1.74, CI 1.11-1.24) and publicly insured (aHR 1.10, CI 1.04-1.17) patients were more likely to be prescribed medication early compared to younger, female and privately insured patients, respectively.

Conclusion and Relevance Many preschool-age children with ADHD seen in primary care in 8 large pediatric health systems were prescribed medications at or shortly after the first documented diagnosis. Future analysis of clinical documentation is needed to understand the reasoning behind early prescription patterns.

Dr. Wallis has been paid as a consultant to Healthy Steps and Thomas Jefferson University. She serves as an expert witness for Kline Spector, LLC. All other authors have no conflicts of interest to disclose.

This work was supported by the Stanford Maternal and Child Health Research Institute and by the National Institute of Mental Health of the National Institutes of Health under grant number K23MH128455 (Dr. Bannett). Dr. Kan was supported by the National Heart, Lung, and Blood Institute (K23HL157615). This study was conducted using PEDSnet, A Pediatric Clinical Research Network. PEDSnet has been developed with funding from the Patient-Centered Outcomes Research Institute (PCORI); PEDSnet participates in PCORnet funded through PCORI award RI-CHOP-01-PS1.

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The multi-site single Institutional Review Board led by Children Hospital of Philadelphia gave ethical approval for this work.

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Conflict of Interest Disclosures (includes financial disclosures): Dr. Wallis has been paid as a consultant to Healthy Steps and Thomas Jefferson University. She serves as an expert witness for Kline Spector, LLC. All other authors have no conflicts of interest to disclose.

Funding/Support: This work was supported by the Stanford Maternal and Child Health Research Institute and by the National Institute of Mental Health of the National Institutes of Health under grant number K23MH128455 (Dr. Bannett). Dr. Kan’s effort was supported by the National Heart, Lung, and Blood Institute (K23HL157615). This study was conducted using PEDSnet, A Pediatric Clinical Research Network. PEDSnet has been developed with funding from the Patient-Centered Outcomes Research Institute (PCORI); PEDSnet’s participation in PCORnet is funded through PCORI award RI-CHOP-01-PS1.

Role of Funder/Sponsor: The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Funders did not have any part in design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Data Availability statement: The datasets generated and analyzed in the current study contain protected patient health information and are therefore not publicly available.

The datasets generated and analyzed in the current study contain protected patient health information and are therefore not publicly available.