Racial and ethnic disparities in care for health system-affiliated physician organizations and non-affiliated physician organizations

Health Serv Res. 2020 Dec;55 Suppl 3(Suppl 3):1107-1117. doi: 10.1111/1475-6773.13581. Epub 2020 Oct 23.


Objective: To assess racial and ethnic disparities in care for Medicare fee-for-service (FFS) beneficiaries and whether disparities differ between health system-affiliated physician organizations (POs) and nonaffiliated POs.

Data sources: We used Medicare Data on Provider Practice and Specialty (MD-PPAS), Medicare Provider Enrollment, Chain, and Ownership System (PECOS), IRS Form 990, 100% Medicare FFS claims, and race/ethnicity estimated using the Medicare Bayesian Improved Surname Geocoding 2.0 algorithm.

Study design: Using a sample of 16 007 POs providing primary care in 2015, we assessed racial/ethnic disparities on 12 measures derived from claims (2 cancer screenings; diabetic eye examinations; continuity of care; two medication adherence measures; three measures of follow-up visits after acute care; all-cause emergency department (ED) visits, all-cause readmissions, and ambulatory care-sensitive admissions). We decomposed these "total" disparities into within-PO and between-PO components using models with PO random effects. We then pair-matched 1853 of these POs that were affiliated with health systems to similar nonaffiliated POs. We examined differences in within-PO disparities by affiliation status by interacting each nonwhite race/ethnicity with an affiliation indicator.

Data collection/extraction methods: Medicare Data on Provider Practice and Specialty identified POs billing Medicare; PECOS and IRS Form 990 identified health system affiliations. Beneficiaries age 18 and older were attributed to POs using a plurality visit rule.

Principal findings: We observed total disparities in 12 of 36 comparisons between white and nonwhite beneficiaries; nonwhites received worse care in 10. Within-PO disparities exceeded between-PO disparities and were substantively important (>=5 percentage points or>=0.2 standardized differences) in nine of the 12 comparisons. Among these 12, nonaffiliated POs had smaller disparities than affiliated POs in two comparisons (P < .05): 1.6 percentage points smaller black-white disparities in follow-up after ED visits and 0.6 percentage points smaller Hispanic-white disparities in breast cancer screening.

Conclusions: We find no evidence that system-affiliated POs have smaller racial and ethnic disparities than nonaffiliated POs. Where differences existed, disparities were slightly larger in affiliated POs.

Keywords: delivery of health care; health care disparities; primary health care; quality of health care; race factors.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Cross-Sectional Studies
  • Delivery of Health Care, Integrated / statistics & numerical data*
  • Ethnicity / statistics & numerical data*
  • Fee-for-Service Plans
  • Female
  • Group Practice / statistics & numerical data*
  • Health Services Research
  • Healthcare Disparities / ethnology
  • Humans
  • Male
  • Medicaid / statistics & numerical data
  • Medicare / statistics & numerical data
  • Middle Aged
  • Primary Health Care / statistics & numerical data*
  • Quality Indicators, Health Care / statistics & numerical data
  • Racial Groups / statistics & numerical data*
  • Residence Characteristics
  • United States