Context: Reliable interpretation of the results of a controlled trial entails setting its results in the context of similar research. A previous study showed that most reports of controlled trials published in 5 general medical journals in May 1997 were deficient in this respect. We assessed the extent to which reports of controlled trials published in the same 5 journals discussed new results in light of the totality of evidence from other controlled trials.
Methods: Assessment of the discussion sections in all 33 reports of randomized trials published during May 2001 in Annals of Internal Medicine, BMJ, JAMA, The Lancet, and The New England Journal of Medicine.
Results: Three reports appeared to have been the first published trials to address the questions studied. In none of the remaining 30 reports were the results of the new trial discussed in the context of an updated systematic review of other trials. Although reference was made to relevant systematic reviews in 3 of these 30 reports, there was no integration, quantitative or qualitative, of the results of the new trials in an update of these reviews. In the remaining 27 reports, there was no evidence that any systematic attempt had been made to set the new results in the context of previous trials.
Conclusions: Between 1997 and 2001, there was no evidence of progress in the proportion of reports of trials published in general medical journals that discussed the new results within the context of, or with reference to, up-to-date systematic reviews of relevant evidence from other controlled trials.