Comparison of reports of randomized controlled trials and systematic reviews in surgical journals: literature review.
OBJECTIVES: Randomized controlled trials and systematic reviews of such trials are the gold standard for assessing the effectiveness of interventions. There have been concerns about the anecdotal evidence underpinning many of the interventions used and introduced into surgical care. The American College of Surgeons has prioritized the need for more trials and systematic reviews of trials. To investigate the assertion that the methodological quality of studies conducted in surgery is in general poor and to assess the possible impact of new policy developments in the US, we sought to compare the number and proportion of published randomized controlled trials and systematic reviews in the leading two US and UK general surgical journals. Two reviewers systematically and independently hand searched all issues of these journals over a 12-month period to identify randomised controlled trials and systematic reviews. DESIGN: Systematic searching and independent abstraction of data from all volumes of the top two general surgical journals published in the USA and the UK in 2004. SETTING: 519 original reports in UK journals and 616 original reports in USA journals. MAIN OUTCOME MEASURES: Number and proportion of randomized controlled trials and systematic reviews. RESULTS: Overall, the proportion of randomized controlled trials in all four journals was 5.6% (95% confidence interval [CI] 4.4-7.0) and 5.2% (95% CI 4.1-6.7) for systematic reviews. For journals published in the UK 29/519 (5.6%) of the publications were reports of randomized controlled trials, and for the USA journals this figure was 34/616 (5.5%); odds ratio [OR]=0.99, 95%CI 0.6-1.6; P=0.96. Systematic reviews were significantly more commonly reported in the UK journals: UK 37/519 (7.1%) versus USA 22/616 (3.6%); OR=0.48, 95%CI 0.3-0.8; P<0.01. CONCLUSIONS: The concerns expressed almost a decade ago remain valid: there are still very few reports of randomized controlled trials and systematic reviews published in leading USA and UK surgical journals, with relatively little difference between these countries in the proportion of reported studies employing these designs. The American College of Surgeons initiative has yet to make an impact.