title: Provider volume and outcomes for oncological procedures.
abstract: BACKGROUND
  Oncological procedures may have better outcomes if performed by high-volume providers.
  
  
  METHODS
  A review of the English language literature incorporating searches of the Medline, Embase and Cochrane collaboration databases was performed. Studies were included if they involved a patient cohort from 1984 onwards, were community or population based, and assessed health outcome as a dependent variable and volume as an independent variable. The studies were also scored quantifiably to assess generalizability with respect to any observed volume-outcome relationship and analysed according to organ system; numbers needed to treat were estimated where possible.
  
  
  RESULTS
  Sixty-eight relevant studies were identified and a total of 41 were included, of which 13 were based on clinical data. All showed either an inverse relationship, of variable magnitude, between provider volume and mortality, or no volume-outcome effect. All but two clinical reports revealed a statistically significant positive relationship between volume and outcome; none demonstrated the opposite.
  
  
  CONCLUSIONS
  High-volume providers have a significantly better outcome for complex cancer surgery, specifically for pancreatectomy, oesphagectomy, gastrectomy and rectal resection.
authors.affiliation: Department of Surgery, Cork University Hospital and University College Cork, Cork, Ireland.
authors.forename: S D
authors.initials: SD
authors.lastname: Killeen
authors.forename: M J
authors.initials: MJ
authors.lastname: O'Sullivan
authors.forename: J C
authors.initials: JC
authors.lastname: Coffey
authors.forename: W O
authors.initials: WO
authors.lastname: Kirwan
authors.forename: H P
authors.initials: HP
authors.lastname: Redmond
mesh_terms: D006276:Health Facility Size; D006761:Hospitals / Q000706:statistics & numerical data*; D006801:Humans; D009369:Neoplasms / Q000401:mortality / Q000601:surgery*; D013514:Surgical Procedures, Operative / Q000706:statistics & numerical data*; D016896:Treatment Outcome; D016526:Workload / Q000706:statistics & numerical data*