title: Case mix in HMOs and fee-for-service systems: the ratio of routine visits to total visits in adult primary care.
mesh_terms: D003361:Cost Allocation; D005249:Fees and Charges; D006279:Health Maintenance Organizations / Q000706:statistics & numerical data*; D006801:Humans; D008962:Models, Theoretical; D010361:Patients / Q000145:classification; D010548:Personal Health Services / Q000706:statistics & numerical data*; D011320:Primary Health Care / Q000191:economics; D012051:Reimbursement Mechanisms; D014481:United States