This paper introduces systematic reviewers and guideline developers to the assessment of evidence in relation to complex interventions and systems when using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach…

This article assesses the conditions for a high risk of bias in overviews of systematic reviews and suggests that the intended function of the overviews could be informative in improving quality…

This commentary draws attention to the composition of the team performing systematic reviews, and its potential biases…