Separate But Not Equal? A Cross-Sectional Study of Segregation by Payor Mix in Academic Primary Care Clinics

Background: At some US Academic Health Centers (AHCs), patients with predominantly Medicaid insurance are seen in one clinic and patients with other insurance are seen in another. The extent of this practice and implications are unknown.

Objective: To estimate the proportion of AHCs that have at least two primary care internal medicine clinics that differ substantially in proportion of patients with Medicaid and to compare patient demographic, staffing, and operational features.

Participants: General internal medicine chiefs and clinic directors at 40 randomly selected US AHCs plus the top 10 AHCs in terms of NIH funding.

Main measure: An AHC was classified as maintaining clinics that differed substantially in the proportion of patients with Medicaid if any two differed by ≥ 40% (absolute). Other criteria were used for pre-specified secondary analyses (e.g., ≥ 30%).

Key results: Thirty-nine of 50 AHCs (78%) participated. Four of 39 (10%; 95% CI, 3 to 24%) had two clinics differing by ≥ 40% in the proportion of patients with Medicaid, eight (21%; 95% CI, 9 to 36%) had clinics differing by ≥ 30%, and 15 (38%; 95% CI, 23 to 55%) had clinics differing by ≥ 20%. Clinics with more patients with Medicaid by any of the three criteria were more likely to employ resident physicians as providers of longitudinal care (with faculty supervision) and more likely to have patients who were Black or Hispanic.

Conclusions: Some US AHCs maintain separate clinics defined by the proportion of patients with Medicaid. Clinics with a higher proportion of patients insured by Medicaid are more likely to employ residents (with faculty oversight), feature residents as providers of longitudinal care, and serve patients who are Black and Hispanic. Further research is needed to understand why some AHCs have primary care clinics distinguishable by insurance mix with the goal of ensuring that racism and discrimination are not root causes.