Grading the quality of evidence in complex interventions: a guide for evidence-based practitioners.

Evidence-based practitioners who want to apply evidence from complex interventions to the care of their patients are often challenged by the difficulty of grading the quality of this evidence. Using the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) approach and an illustrative example, we propose a framework for evaluating the quality of evidence that depends on obtaining feedback from the evidence user (eg, guideline panel) to inform: (1) proper framing of the question, (2) judgements about directness and consistency of evidence and (3) the need for additional contextual and qualitative evidence. Using this framework, different evidence users and based on their needs would consider the same evidence as high, moderate, low or very low.