title: Impact of Patient Characteristics on Hospital-Level Outcomes Assessment in Congenital Heart Surgery.
abstract: BACKGROUND
  Accurate hospital outcome measures in congenital heart surgery are important to multiple initiatives. While methods have been developed to account for differences in procedural case-mix, characteristics patients bring into the operation that may also vary across hospitals and influence outcome have received less attention. We evaluated the impact of these characteristics in a large cohort.
  
  
  METHODS
  Patients undergoing congenital heart surgery at centers participating in The Society of Thoracic Surgeons Congenital Heart Surgery Database (2010 to 2013) with adequate data quality were included. Variation across hospitals in important patient characteristics was examined, and hospital operative mortality rates were compared with and without adjustment for patient characteristics.
  
  
  RESULTS
  Overall, 86 centers (52,224 patients) were included. There was greater than twofold variation across hospitals for nearly all patient characteristics examined. For example, the proportion of a center's surgical population comprised of neonates ranged from 12.8% to 26.6% across hospitals; the proportion with a non-cardiac anomaly ranged from 0.7% to 5.0%. When hospital mortality rankings were evaluated based on "standard" (adjustment for differences in procedural case-mix alone) versus "full" models (adjustment for both differences in procedural case-mix and patient characteristics), 14.0% changed their ranking for mortality by 20 or greater positions, 34.9% of centers changed which mortality quartile they were classified in, and 14.0% changed their statistical classification (statistically higher, lower, or same-as-expected mortality).
  
  
  CONCLUSIONS
  Characteristics of patients undergoing congenital heart surgery vary across centers and impact hospital outcomes assessment. Methods to assess outcomes and relative performance should account for these characteristics.
authors.affiliation: Department of Pediatrics and Communicable Diseases, C.S. Mott Children's Hospital, Ann Arbor, Michigan. Electronic address: pasquali@med.umich.edu.
authors.forename: Sara K
authors.initials: SK
authors.lastname: Pasquali
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland; Johns Hopkins All Children's Heart Institute, Saint Petersburg, Tampa, and Orlando, Florida; Florida Hospital for Children, Orlando, Florida.
authors.forename: Marshall L
authors.initials: ML
authors.lastname: Jacobs
authors.affiliation: Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Sean M
authors.initials: SM
authors.lastname: O'Brien
authors.affiliation: Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Xia
authors.initials: X
authors.lastname: He
authors.affiliation: Division of Cardiothoracic Surgery, Department of Surgery, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
authors.forename: J William
authors.initials: JW
authors.lastname: Gaynor
authors.affiliation: Department of Pediatrics and Communicable Diseases, C.S. Mott Children's Hospital, Ann Arbor, Michigan.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Gaies
authors.affiliation: Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina.
authors.forename: Eric D
authors.initials: ED
authors.lastname: Peterson
authors.affiliation: Department of Cardiac Surgery, University of Michigan Medical School, Ann Arbor, Michigan.
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Hirsch-Romano
authors.affiliation: Department of Cardiac Surgery, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts.
authors.forename: John E
authors.initials: JE
authors.lastname: Mayer
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, Johns Hopkins University School of Medicine, Baltimore, Maryland; Johns Hopkins All Children's Heart Institute, Saint Petersburg, Tampa, and Orlando, Florida; Florida Hospital for Children, Orlando, Florida.
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Jacobs
mesh_terms: D006348:Cardiac Surgical Procedures; D005260:Female; D006330:Heart Defects, Congenital / Q000601:surgery*; D006761:Hospitals; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D017063:Outcome Assessment, Health Care