In this last paper of the series about risk of bias assessment, we introduce the application of risk of bias assessment results. Risk of bias assessment is one of the key steps in the assessment of quality of evidence. The risk of bias assessment results could be the "diagnosis" of individual studies, which helps decision making related to the inclusion and exclusion of individual studies, as well as the data analysis in the systematic review process. This paper focuses on how to incorporate risk of bias assessment results in the GRADE assessment for quality of evidence, including the principles and the tips for the application.