Produced by Dr Kerry Dwan of the MRC North West Hub for Trials Methodology Research, which is based in the Department, the podcast is based on the Cochrane Methodology Review Comparison of protocols and registry entries to published reports for randomised controlled trials.
The non-reporting of a piece of research and the selective reporting of only some of its findings has been identified as a problem for research studies such as randomised trials and systematic reviews of these. If the decision about what to report and what to keep unpublished is based on the results obtained in the trial, this will lead to bias and potentially misleading conclusions by users of the research.
One way to see if there might be discrepancies between what was planned or done in a trial and what is eventually reported is to compare the protocol or entry in a trial registry for the trial with the content of its published report. This might reveal that changes were made between the registration and planning of the trial and its eventual analysis. Any such changes should be described in the published report, to reassure readers and others who will use the trial’s results that the risk of bias has been kept low.
Dr Dwan said: “This Cochrane methodology review examines the reporting of randomised trials by reviewing research done by others in which the information in protocols or trial registry entries were compared to that in the published reports for groups of trials, to see if this detected any inconsistencies for any aspects of the trials.
“We included 16 studies in this review and the results indicate that there are often discrepancies between the information provided in protocol and trial registry entries and that contained in the published reports for randomised trials. These discrepancies cover many aspects of the trials and are not explained or stated in the published reports.”
Click here to listen to the podcast.