title: A comparative study of quality outcomes in freestanding ambulatory surgery centers and hospital-based outpatient departments: 1997-2004.
abstract: OBJECTIVE
  To compare quality outcomes from surgical procedures performed at freestanding ambulatory surgery centers (ASCs) and hospital-based outpatient departments (HOPDs).
  
  
  METHODS
  Patient-level ambulatory surgery (1997-2004), hospital discharge (1997-2004), and vital statistics data (1997-2004) for the state of Florida were assembled and analyzed.
  
  
  METHODS
  We used a pooled, cross-sectional design. Logistic regressions with time fixed-effects were estimated separately for the 12 most common ambulatory surgical procedures. Our quality outcomes were risk-adjusted 7-day and 30-day mortality and 7-day and 30-day unexpected hospitalizations. Risk-adjustment for patient demographic characteristics and severity of illness were calculated using the DCG/HCC methodology adjusting for primary diagnosis only and separately for all available diagnoses.
  
  
  RESULTS
  Although neither ASCs nor HOPDs performed better overall, we found some difference by procedure that varied based on the risk-adjustment approach used.
  
  
  CONCLUSIONS
  There appear to be important variations in quality outcomes for certain procedures, which may be related to differences in organizational structure, processes, and strategies between ASCs and HOPDs. The study also confirms the importance of risk-adjustment for comorbidities when using administrative data, particularly for procedures that are sensitive to differences in severity.
authors.affiliation: Division of Health Affairs, Department of Family Medicine and Rural Health, Florida State University College of Medicine, 1115 West Call Street, Suite 3200, Tallahassee, FL 32306-4300, USA.
authors.forename: Askar S
authors.initials: AS
authors.lastname: Chukmaitov
authors.forename: Nir
authors.initials: N
authors.lastname: Menachemi
authors.forename: L Steven
authors.initials: LS
authors.lastname: Brown
authors.forename: Charles
authors.initials: C
authors.lastname: Saunders
authors.forename: Robert G
authors.initials: RG
authors.lastname: Brooks
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000554:Ambulatory Care Facilities / Q000458:organization & administration* / Q000592:standards; D000556:Ambulatory Surgical Procedures; D003430:Cross-Sectional Studies; D005260:Female; D005431:Florida; D006801:Humans; D007348:Insurance, Health / Q000706:statistics & numerical data; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009026:Mortality; D010043:Outcome and Process Assessment, Health Care / Q000458:organization & administration; D010044:Outpatient Clinics, Hospital / Q000458:organization & administration; D010351:Patient Discharge / Q000706:statistics & numerical data; D011787:Quality of Health Care / Q000458:organization & administration* / Q000592:standards; D020379:Risk Adjustment; D012720:Severity of Illness Index; D012737:Sex Factors; D012959:Socioeconomic Factors; D055815:Young Adult