title: Hospital variation in 30-day mortality after colorectal cancer surgery in denmark: the contribution of hospital volume and patient characteristics.
abstract: OBJECTIVE
  This study examines variation between hospitals in 30-day mortality after surgery for colorectal cancer (CRC) in Denmark and explores whether hospital volume and patient characteristics contribute to any variation between hospitals.
  
  
  BACKGROUND
  Little is known about the variation between hospitals in 30-day mortality after CRC surgery, and the impact of treatment and patient characteristics that might contribute to such variation.
  
  
  METHODS
  Hospital variation was quantified using a multilevel approach on data derived from a nationwide database of all adenocarcinomas of colon and rectum diagnosed in Denmark in 2001 to 2004. These data were linked to several central registers providing information on patient's socioeconomic status, comorbidity, and use of medication. In total 11,287 patients, who underwent surgery at any of the 43 surgical departments were included.
  
  
  RESULTS
  Hospitals varied from 3.5% to 44.1% in 30-day mortality after emergency colon cancer surgery, and the multilevel analysis showed that emergency patients were 5 times [odd ratio (OR) = 4.6)] as likely to die within 30 days in hospitals with the worst performance compared to those with the best performance. The American Society of Anesthesiologists (ASA) score increased the variation between hospitals (OR = 5.8), whereas the other potential explanatory variables had no effect on the variation. For patients who had elective surgery for colon and rectal cancer the variation in 30-day mortality between hospitals was small and nonsignificant.
  
  
  CONCLUSIONS
  Hospital variation in 30-day mortality after CRC surgery are due to differences in hospitals' ability to take care of emergency patients, especially those with high ASA scores.
authors.affiliation: Research Center for Prevention and Health, Glostrup University Hospital, Denmark. M.osler@dadlnet.dk
authors.forename: Merete
authors.initials: M
authors.lastname: Osler
authors.forename: Lene H
authors.initials: LH
authors.lastname: Iversen
authors.forename: Anders
authors.initials: A
authors.lastname: Borglykke
authors.forename: Solvej
authors.initials: S
authors.lastname: Mårtensson
authors.forename: Signe
authors.initials: S
authors.lastname: Daugbjerg
authors.forename: Henrik
authors.initials: H
authors.lastname: Harling
authors.forename: Torben
authors.initials: T
authors.lastname: Jørgensen
authors.forename: Birgitte
authors.initials: B
authors.lastname: Frederiksen
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000401:mortality / Q000601:surgery; D016009:Chi-Square Distribution; D003082:Colectomy / Q000379:methods / Q000401:mortality*; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000401:mortality* / Q000601:surgery*; D016208:Databases, Factual; D003718:Denmark; D017558:Elective Surgical Procedures / Q000706:statistics & numerical data; D004638:Emergency Treatment / Q000706:statistics & numerical data; D005260:Female; D019538:Health Care Surveys; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D016015:Logistic Models; D008297:Male; D018579:Patient Selection; D011183:Postoperative Complications / Q000401:mortality* / Q000503:physiopathology; D019984:Quality Indicators, Health Care; D018570:Risk Assessment; D013503:Surgery Department, Hospital / Q000592:standards / Q000639:trends; D016019:Survival Analysis; D013997:Time Factors