Use of systematic reviews to justify the conduct of urology clinical trials

Background: Some have estimated billions of dollars each year are lost to health research worldwide. Given the increased amount of research being funded in the field of urology, reducing the amount of research waste is vital. Systematic reviews (SRs) are an essential tool in aiding in reducing waste in research; they are a comprehensive summary of the current data on a clinical question. Given the significant costs and time-intensive nature of randomized controlled trials (RCTs), it is critical that the research questions be carefully selected and prioritized to avoid unnecessary duplication of effort. In this study, we performed a review of urology RCTs to determine whether the trial authors reported having first consulted available SRs to establish the need for conducting their trial. Secondarily we evaluated the ways in which SRs were incorporated into clinical trial reports.

Methods: On December 13, 2019, one of us (BJ) conducted a PubMed search for RCTs published from 2014 to 2019 in the top four urology journals according to their Google Scholar h5-index. These journals were European Urology, BJU international, The Journal of Urology, and Urology. Two of us (SS and AW) underwent training prior to screening and extraction from authors MV and BJ. RCTs were screened, and data was extracted in masked and duplicated fashion as recommended by the Cochrane Handbook. Then each cited SR was evaluated for if it was justification for conducting the trial based on the context the SR was used.

Results: The search returned 566 articles, 276 were included. Overall 61.2% (169/276) the included trials cited a SR though 46.0% (127/276) of the included studies did not cite a SR as justification for conducting the trial. The 403 citations most commonly were found in the discussion 50.8% (205/403) while very few SRs were cited in the methods of trials 3.7% (15/403) A significant association between verbatim justification and type of intervention (x2=20.23, p=0.017) with 58.1% of 'other' having a SRs verbatim justification, but only 33.1% (39/118) of drug trials having SRs verbatim justification was noted. Trials published in the journal of European Urology were found to contain the most citations of SR’s for verbatim justification 36.1% (87/241).

Conclusion: Less than half of the included RCTs cited a SR as justification for conducting the trial. These findings show that even with the increasing number of SRs available and more than a hundred Cochrane urology reviews published there is a disconnect between trialist and use of the existing evidence in trials conducted in the field of urology. If new trials were required to support their studies with SRs we believe this would greatly reduce the amount of research waste within clinical research.