title: Feasibility of randomized controlled trials in liver surgery using surgery-related mortality or morbidity as endpoint.
abstract: BACKGROUND
  There is a shortage of randomized controlled trials (RCTs) on which to base guidelines in liver surgery. The feasibility of conducting an adequately powered RCT in liver surgery using the dichotomous endpoints surgery-related mortality or morbidity was examined.
  
  
  METHODS
  Articles published between January 2002 and November 2007 with mortality or morbidity after liver surgery as primary endpoint were retrieved. Sample size calculations for a RCT aiming to show a relative reduction of these endpoints by 33, 50 or 66 per cent were performed.
  
  
  RESULTS
  The mean operative mortality rate was 1.0 per cent and the total morbidity rate 28.9 per cent; mean rates of bile leakage and postresectional liver failure were 4.4 and 2.6 per cent respectively. The smallest numbers of patients needed in each arm of a RCT aiming to show a 33 per cent relative reduction were 15 614 for operative mortality, 412 for total morbidity, 3446 for bile leakage and 5924 for postresectional liver failure.
  
  
  CONCLUSIONS
  The feasibility of conducting an adequately powered RCT in liver surgery using outcomes such as mortality or specific complications seems low. Conclusions of underpowered RCTs should be interpreted with caution. A liver surgery-specific composite endpoint may be a useful and clinically relevant solution to pursue.
authors: Department of Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands.
authors: M A J
authors: MA
authors: van den Broek
authors: R M
authors: RM
authors: van Dam
authors: M
authors: M
authors: Malagó
authors: C H C
authors: CH
authors: Dejong
authors: G J P
authors: GJ
authors: van Breukelen
authors: S W M
authors: SW
authors: Olde Damink
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D005240:Feasibility Studies; D005260:Female; D006498:Hepatectomy / Q000401:mortality / Q000706:statistics & numerical data; D006801:Humans; D007223:Infant; D008113:Liver Neoplasms / Q000401:mortality / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic / Q000401:mortality; D011183:Postoperative Complications / Q000209:etiology / Q000401:mortality; D016032:Randomized Controlled Trials as Topic / Q000401:mortality*; D055815:Young Adult