title: Discontinuation and non-publication of surgical randomised controlled trials: observational study.
abstract: OBJECTIVE
  To determine the rate of early discontinuation and non-publication of randomised controlled trials involving patients undergoing surgery.
  
  
  METHODS
  Cross sectional observational study of registered and published trials.
  
  
  METHODS
  Randomised controlled trials of interventions in patients undergoing a surgical procedure.
  
  
  METHODS
  The ClinicalTrials.gov database was searched for interventional trials registered between January 2008 and December 2009 using the keyword "surgery". Recruitment status was extracted from the ClinicalTrials.gov database. A systematic search for studies published in peer reviewed journals was performed; if they were not found, results posted on the ClinicalTrials.gov results database were sought. Email queries were sent to trial investigators of discontinued and unpublished completed trials if no reason for the respective status was disclosed.
  
  
  METHODS
  Trial discontinuation before completion and non-publication after completion. Logistic regression was used to determine the effect of funding source on publication status, with adjustment for intervention type and trial size.
  
  
  RESULTS
  Of 818 registered trials found using the keyword "surgery", 395 met the inclusion criteria. Of these, 21% (81/395) were discontinued early, most commonly owing to poor recruitment (44%, 36/81). The remaining 314 (79%) trials proceeded to completion, with a publication rate of 66% (208/314) at a median time of 4.9 (interquartile range 4.0-6.0) years from study completion to publication search. A further 6% (20/314) of studies presented results on ClinicalTrials.gov without a corresponding peer reviewed publication. Industry funding did not affect the rate of discontinuation (adjusted odds ratio 0.91, 95% confidence interval 0.54 to 1.55) but was associated with a lower odds of publication for completed trials (0.43, 0.26 to 0.72). Investigators' email addresses for trials with an uncertain fate were identified for 71.4% (10/14) of discontinued trials and 83% (101/122) of unpublished studies. Only 43% (6/14) and 20% (25/122) replies were received. Email responses for completed trials indicated 11 trials in press, five published studies (four in non-indexed peer reviewed journals), and nine trials remaining unpublished.
  
  
  CONCLUSIONS
  One in five surgical randomised controlled trials are discontinued early, one in three completed trials remain unpublished, and investigators of unpublished studies are frequently not contactable. This represents a waste of research resources and raises ethical concerns regarding hidden clinical data and futile participation by patients with its attendant risks. To promote future efficiency and transparency, changes are proposed to research governance frameworks to overcome these concerns.
authors.affiliation: University of Leeds, School of Medicine, Leeds LS2 9JT, UK.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Chapman
authors.affiliation: University of Birmingham, College of Medical and Dental Sciences, Birmingham B15 2TH, UK.
authors.forename: Bryony
authors.initials: B
authors.lastname: Shelton
authors.affiliation: St George's University Hospital Medical School, London SW17 0RE, UK.
authors.forename: Humza
authors.initials: H
authors.lastname: Mahmood
authors.affiliation: Royal Free Hospital NHS Trust, Barnet Hospital Campus, High Barnet EN5 3DJ, UK.
authors.forename: J Edward
authors.initials: JE
authors.lastname: Fitzgerald
authors.affiliation: Clinical Surgery, University of Edinburgh, Edinburgh EH16 4SA, UK.
authors.forename: Ewen M
authors.initials: EM
authors.lastname: Harrison
authors.affiliation: University of Birmingham, College of Medical and Dental Sciences, Birmingham B15 2TH, UK aneelbhangu@doctors.org.uk.
authors.forename: Aneel
authors.initials: A
authors.lastname: Bhangu
mesh_terms: D003430:Cross-Sectional Studies; D013502:General Surgery; D006801:Humans; D018579:Patient Selection; D011640:Public Policy; D011643:Publishing / Q000706:statistics & numerical data*; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data*; D012109:Research Support as Topic