Descriptive Observational Study of Trends in Subspecialty Utilization Among the Medicaid and Commercially Insured Pediatric Population in New York City

Objective: As the pediatric population on Medicaid tends to use less subspecialty care compared with those with commercial insurance, we sought to determine whether the integration of subspecialty practices increased Medicaid utilization overall and by race and ethnicity in 1 academic medical center. Research Design: A retrospective observational study using medical record data spanning 7 years across 4 time periods: (1) preintegration (June 2018–February 2020); (2) COVID-related public health emergency only (PHE) (March 2020–December 2021); (3) overlap of PHE and integration (January 2022–May 2024); and (4) postintegration (June 2024–May 2025). Subjects: Patients aged 20 or younger with at least 2 subspecialty visits within the year. At least 30 days apart. Measures: The primary outcome was the proportion of visits by those on Medicaid, analyzed using segmented regression, which modeled the time series with demarcation of time periods. It estimated the outcome at the start of, and the trend across, each time period. Results: Among the pediatric population of 15,206, 46.3% were female, 23.3% Hispanic, 36.6% non-Hispanic White, and 6.2% non-Hispanic Black. The adjusted (age, sex, and subspecialty) proportion of Medicaid visits at each time period was preintegration: 25.04%; PHE only: 13.58%; overlap: 24.29%; and postintegration: 36.18%. The adjusted risk ratio (ARR) of post- to preintegration was ARR: 1.53 [CI: 1.40–1.67]. There were significant increases (19%–147%) in Medicaid use across races and ethnicities from pre- to postintegration. Conclusion: Integration of subspecialty clinics increased utilization among the pediatric population with Medicaid. The PHE diminished subspecialty use, but subsequent increases have benefited Medicaid patients across all races and ethnicities.