title: HMO study refutes single national plan.
mesh_terms: D001290:Attitude; D006264:Health Benefit Plans, Employee / Q000458:organization & administration*; D006279:Health Maintenance Organizations / Q000458:organization & administration*; D006801:Humans; D007348:Insurance, Health / Q000458:organization & administration*; D011641:Public Relations; D014481:United States