title: Gynaecologic surgery from uncertainty to science: evolution of randomized control trials.
abstract: BACKGROUND
  It is now accepted that both medical and surgical practice should be based on reliable and sound clinical evidence. However, randomized control trials comparing surgical interventions have been associated with many problems. The aim of this review is to assess if there has been progress made in establishing the evidence base for surgical interventions in gynaecology.
  
  
  METHODS
  Relevant reviews were identified from Cochrane Database of Systematic Reviews (Issue , 2006) and data from individual randomized control trials extracted. Chi-squared test was used to compare quality pre- and post-Consolidated Standards of Reporting Trials (CONSORT) statement. Meta-regression analyses were performed to test the hypothesis that effect size decreased over time. Further multiple linear regression analyses were used to test the hypothesis that precision increased over time and finally a logistic regression model was used to estimate whether treatment effects differed between trials with and without allocation concealment.
  
  
  RESULTS
  Twenty-three relevant reviews were identified, including 94 trials. The proportion of studies reporting allocation concealment significantly increased after the introduction of the CONSORT statement (P = 0.002). There was a trend towards improvement in precision over time. Similarly, there was a reduction in size of treatment effect over time (log of the ratio of odds ratios per year 0.96; 95% confidence interval 0.93-0.99, P = 0.04).
  
  
  CONCLUSIONS
  Gynaecologic surgical practice appears to be benefiting from improvement in its research base in a subject where practitioners do not participate readily in randomized evaluation.
authors.affiliation: Department of Reproductive and Child Health, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. taraselman@blueyonder.co.uk
authors.forename: Tara J
authors.initials: TJ
authors.lastname: Selman
authors.forename: Neil P
authors.initials: NP
authors.lastname: Johnson
authors.forename: Javier
authors.initials: J
authors.lastname: Zamora
authors.forename: Khalid S
authors.initials: KS
authors.lastname: Khan
mesh_terms: D015982:Bias; D019317:Evidence-Based Medicine; D005260:Female; D013509:Gynecologic Surgical Procedures; D006801:Humans; D016032:Randomized Controlled Trials as Topic