| Evidence classification method： |
Levels of Evidence
Grade I (high) High-quality randomized controlled clinical trials (RCT), authoritative guidelines, high-quality systematic reviews and meta-analysis
Grade Ⅱ (medium) RCT studies, cohort studies, case series studies and case-control studies with certain limitations
Grade Ⅲ (low) Case report, expert opinion text
Levels of recommendations
A (strong) Most doctors and policy makers will adopt this plan
B (moderate) Most role-players will adopt this plan, but there are still certain role-players who will not adopt it. A decision must be made based on the specific circumstances
C (weak) Insufficient evidence requires doctors and policymakers to discuss the recommendation and decide together |
