Stats & facts. The gatekeeping question.
D000328:Adult; D003258:Consumer Behavior / Q000706:statistics & numerical data; D003625:Data Collection; D020793:Gatekeeping / Q000706:statistics & numerical data*; D019538:Health Care Surveys; D006801:Humans; D008329:Managed Care Programs / Q000706:statistics & numerical data*; D008511:Medicine / Q000706:statistics & numerical data; D013038:Specialization; D016896:Treatment Outcome; D014481:United States