Comparison of Hospital Outcomes for Patients Treated by Allopathic Versus Osteopathic Hospitalists An Observational Study

Background: The United States has 2 types of degree programs that educate physicians: allopathic and osteopathic medical schools. Objective: To determine whether quality and costs of care differ between hospitalized Medicare patients treated by allopathic or osteopathic physicians. Design: Retrospective observational study. Setting: Medicare claims data. Patients: 20% random sample of Medicare fee- for-service beneficiaries hospitalized with a medical condition during 2016 to 2019 and treated by hospitalists. Measurements: The primary outcome was 30-day patient mortality. The secondary outcomes were 30-day readmission, length of stay (LOS), and health care spending (Part B spending). Multivariable regression models adjusted for patient and physician characteristics and their hospital-level averages (to effectively estimate differences within hospitals) were estimated. Results: Of 329 510 Medicare admissions, 253 670 (77.0%) and 75 840 (23.0%) received care from allopathic and osteopathic physicians, respectively. The results can rule out important differences in quality and costs of care between allopathic versus osteopathic physicians for patient mortality (adjusted mortality, 9.4% for allopathic physicians vs. 9.5% [reference] for osteopathic hospitalists; average marginal effect [AME], similar to 0.1 percentage point [95% CI, similar to 0.4 to 0.1 percentage point]; P = 0.36), readmission (15.7% vs. 15.6%; AME, 0.1 percentage point [CI, similar to 0.4 to 0.3 percentage point; P = 0.72), LOS (4.5 vs. 4.5 days; adjusted difference, similar to 0.001 day [CI, similar to 0.04 to 0.04 day]; P = 0.96), and health care spending ($1004 vs. $1003; adjusted difference, $ 1 [CI, similar to$8 to $10]; P = 0.85). Limitation: Data were limited to elderly Medicare patients hospitalized with medical conditions. Conclusion: The quality and costs of care were similar between allopathic and osteopathic hospitalists when they cared for elderly patients and worked as the principal physician in a team of health care professionals that often included other allopathic and osteopathic physicians.