Widely different referral rates have little effect on outcomes.
D017048:Health Care Costs; D006304:Health Status; D006760:Hospitalization; D006801:Humans; D008329:Managed Care Programs / Q000458:organization & administration*; D009518:New York; D017063:Outcome Assessment, Health Care; D017060:Patient Satisfaction; D012017:Referral and Consultation / Q000706:statistics & numerical data*