Quality Assessment of RCTs in Cochrane Breast Cancer Review group

Introduction: High-quality systematic reviews provide dependable evidence for medical interventions. Bias in Randomized controlled trials may overvalue or undervalue the efficacy of an intervention. There are few systematic reviews which contain all eligible articles on the special issue and thus present the highest quality evidence. Since breast cancer is the most common neoplasm in females, we aim to determine the variations in the risk of bias for randomized controlled trials included in The Cochrane breast cancer review group. Methods: This study was done as a review of RCTs included in Cochrane breast cancer systematic reviews until October 2015. Overall, 47 reviews which included 587 RCTs, were studied to determine the risk of selection, performance, detection, attrition and reporting bias by The Cochrane Collaboration s “Risk of Bias” tool. Then, data was analyzed by Microsoft Excel 2013 for frequency analyses. Finally, it was assessed if authors have gotten a specific conclusion or not. Findings: The search identified 50 reviews that 3 of them were excluded because of no RCTs inclusion. Finally, 587 RCTs were included for analysis. This study showed that the most and the least reported bias were allocation concealment and detection bias, respectively, which was reported in 93.6% and 48.2% of RCTs. Among 47 included systematic reviews, 33 of them could get a conclusion due to an adequate amount of evidence for their included RCTs and other 14 reviews needed more studies to get a conclusion. Conclusion: According to the results, there was not any study with the only low risk of bias in all categories of bias, so it’s concluded that adequate high evidence-based studies such as RCTs are missing in the field of breast cancer.