Ambulatory severity index: development of an ambulatory case mix system.
D000553:Ambulatory Care / Q000145:classification*; D005069:Evaluation Studies as Topic; D010044:Outpatient Clinics, Hospital / Q000191:economics*; D011445:Prospective Payment System; D012720:Severity of Illness Index; D012959:Socioeconomic Factors; D014481:United States