How to Correctly Understand and Use the Low-quality Evidence to Formulate Recommendations in Guidelines

The essence of clinical practice guidelines lies in their recommendations. It is common to find strong recommendations supported by low-quality evidence in current published guidelines. There is a typical misunderstanding among medical professionals that without high-quality evidence, it is impossible to develop high-quality guidelines or only expert consensus can be developed. Based on the GRADE approach, this paper explains the concept and clinical significance of low-quality evidence, and introduces the methods for formulating recommendations based on low-quality evidence in guidelines, with the aim to provide reference for guideline developers and users in China.