title: Intra-operative vs pre-operative endoscopic sphincterotomy in patients with gallbladder and common bile duct stones: cost-utility and value-of-information analysis.
abstract: BACKGROUND
  Patients with gallbladder and common bile duct stones are generally treated by pre-operative endoscopic sphincterotomy (ES) followed by laparoscopic cholecystectomy (POES). Recently, a meta-analysis has shown that intra-operative ES during laparoscopic cholecystectomy (IOES) results in fewer complications than POES, with similar efficacy. The cost effectiveness of IOES versus POES is unknown.
  
  
  OBJECTIVE
  The objective of this study was to compare the cost effectiveness of IOES versus POES from the UK NHS perspective.
  
  
  METHODS
  A decision-tree model estimating and comparing costs to the UK NHS and QALYs gained following a policy of either IOES or POES was developed with a time horizon of 3 years. Uncertainty was investigated with probabilistic sensitivity analysis, and the expected value of perfect information (EVPI) and partial information (EVPPI) were also calculated.
  
  
  RESULTS
  IOES was less costly than POES (approximately -£623 per patient [year 2008 values]) and resulted in similar quality of life (+0.008 QALYs per patient) as POES. Given a willingness-to-pay threshold of £20 000 per QALY gained, there was a 92.9% probability that IOES is cost effective compared with POES. Full implementation of IOES could save the NHS £2.8 million per annum. At a willingness to pay of £20 000 per QALY gained, the 10-year population EVPI was estimated at £0.6 million.
  
  
  CONCLUSIONS
  IOES appears to be cost effective compared with POES.
authors.affiliation: Hepatopancreatobiliary and Liver Transplant Surgery, University Department of Surgery, Royal Free Campus UCL Medical School, London, UK. kurinchi2k@hotmail.com
authors.forename: Kurinchi
authors.initials: K
authors.lastname: Gurusamy
authors.forename: Edward
authors.initials: E
authors.lastname: Wilson
authors.forename: Andrew K
authors.initials: AK
authors.lastname: Burroughs
authors.forename: Brian R
authors.initials: BR
authors.lastname: Davidson
mesh_terms: D001659:Biliary Tract / Q000503:physiopathology*; D001662:Biliary Tract Surgical Procedures / Q000191:economics; D003362:Cost-Benefit Analysis; D042882:Gallstones / Q000601:surgery*; D006801:Humans; D007430:Intraoperative Care; D011300:Preoperative Care; D011788:Quality of Life; D016717:Sphincterotomy, Endoscopic / Q000191:economics*; D013222:State Medicine; D006113:United Kingdom