Objective: Cochrane Library provides a powerful and authoritative database to aid medical decision making. We aimed to evaluate the quality of clinical trials and systematic reviews recorded in the Cochrane urology cancers group.
Material and methods: This analytic cross-sectional study was conducted on 44 published systematic reviews of the Cochrane urology group which were published until May 2020. In the current study, we selected the urological cancer reviews. All types of biases in the understudied randomized controlled trials (RCTs) or quasi-RCTs of these systematic reviews were evaluated using the Cochrane appraisal checklist. We also separated and stratified the types of biases in the included studies. In addition, the quality of systematic reviews was assessed using the Joanna Briggs Institute (JBI) appraisal checklist.
Results: A total of 44 systematic reviews and their understudied 340 RCTs were evaluated. On the basis of the JBI appraisal checklist results, 93.2% of systematic reviews had high quality. In terms of the quality of understudied RCTs in these reviews, the common prevalent risk of bias of the understudied RCTs or quasi- RCTs was unclear selection bias (allocation concealment and random sequence generation). The highest risk of bias was seen in the blinding of participants and personnel (performance bias).
Conclusion: Although most Cochrane urological cancer reviews had high quality, performance bias was the highest one in their understudied RCTs. Regarding it and considering the increasing unclear risk of detection, attrition, and reporting biases, it is obvious that they have structural deficiencies; therefore, it is recommended to observe integrity principles for preventing research misconduct.