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 paper, entitled Considerations of complexity in rating certainty of evidence in systematic reviews: a primer on using the GRADE approach in global health, published in BMJ Global Health, is part of a new World Health Organisation paper series on processes and methods for developing guidelines on complex health interventions and on interventions delivered in complex systems.