Analysis of North Carolina Medicaid Claims Data to Simulate a Pediatric Accountable Care Organization

IMPORTANCE: Despite momentum for pediatric value-based payment models, little is known about tailoring design elements to account for the unique needs and utilization patterns of children and young adults. OBJECTIVE: To simulate attribution to a hypothetical pediatric accountable care organization (ACO) and describe baseline demographic characteristics, expenditures, and utilization patterns over the subsequent year. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used Medicaid claims data for children and young adults aged 1 to 20 years enrolled in North Carolina Medicaid at any time during 2017. Children and young adults receiving at least 50% of their primary care at a large academic medical center (AMC) in 2017 were attributed to the ACO. Data were analyzed from April 2020 to March 2021. MAIN OUTCOMES AND MEASURES: Primary outcomes were total cost of care and care utilization during the 2018 performance year. RESULTS: Among 930 266 children and young adults (377 233 children [40.6%] aged 6-12 years; 470 612 [50.6%] female) enrolled in Medicare in North Carolina in 2017, 27 290 children and young adults were attributed to the ACO. A total of 12 306 Black non-Hispanic children and young adults (45.1%), 6308 Hispanic or Latinx children and young adults (23.1%), and 6531 White non-Hispanic children and young adults (23.9%) were included. Most attributed individuals (23 133 individuals [84.7%]) had at least 1 claim in the performance year. The median (IQR) total cost of care in 2018 was $347 ($107-$1123); 272 individuals (1.0%) accounted for nearly half of total costs. Compared with children and young adults in the lowest-cost quartile, those in the highest-cost quartile were more likely to have complex medical conditions (399 individuals [6.9%] vs 3442 individuals [59.5%]) and to live farther from the AMC (median [IQR distance, 6.0 [4.6-20.3] miles vs 13.9 [4.6-30.9] miles). Total cost of care was accrued in home (43%), outpatient specialty (19%), inpatient (14%) and primary (8%) care. More than half of attributed children and young adults received care outside of the ACO; the median (IQR) cost for leaked care was $349 ($130-$1326). The costliest leaked encounters included inpatient, ancillary, and home health care, while the most frequently leaked encounters included behavioral health, emergency, and primary care. CONCLUSIONS AND RELEVANCE: This cohort study found that while most children attributed to the hypothetical Medicaid pediatric ACO lived locally with few health care encounters, a small group of children with medical complexity traveled long distances for care and used frequent and costly home-based and outpatient specialty care. Leaked care was substantial for all attributed children, with the cost of leaked care being higher than the total cost of care. These pediatric-specific clinical and utilization profiles have implications for future pediatric ACO design choices related to attribution, accounting for children with high costs, and strategies to address leaked care.