Understanding Grading Systems for Clinical Recommendations
GRADE System Components
Clinical practice guidelines use a two-part grading system to communicate the strength of evidence and recommendations. 1
Quality of Evidence Grades
The evidence supporting each recommendation is assigned one of four quality grades:
- Grade A (High Quality): High confidence that the estimated effects are close to the true effects; further research is very unlikely to change confidence in the estimate 1
- Grade B (Moderate Quality): Moderate confidence in the estimated effects; further research may have an important impact on confidence and may change the estimate 1
- Grade C (Low Quality): Limited confidence in the estimated effects; further research is very likely to have an important impact on confidence and is likely to change the estimate 1
- Grade D (Very Low Quality): Very little confidence in the estimated effects; the estimate is very uncertain 1
Strength of Recommendation Levels
Beyond evidence quality, recommendations receive a strength rating that reflects confidence that benefits outweigh harms:
- Level 1 ("We recommend"): Strong recommendation indicating this action should be applied to most patients; practitioners can have confidence that implementing this recommendation has more benefit than risk 1
- Level 2 ("We suggest"): Conditional recommendation indicating different choices may be appropriate for different patients based on individual values and preferences; requires substantial patient discussion and shared decision-making 1
Additional Recommendation Types
Good Practice Points (GPP): Ungraded statements developed when evidence quality is too low for formal grading, but the work group determines guidance is important for routine practice 1
Opinion Statements: Ungraded recommendations provided when insufficient evidence exists but expert consensus suggests guidance would benefit patients and practitioners 1
Factors Beyond Evidence Quality
When assigning recommendation strength, guideline developers consider multiple factors beyond just evidence quality: patient values and preferences, balance of benefits and harms, cost and resources required for implementation, acceptability to stakeholders, feasibility of implementation, and health equity implications 1
Practical Implications by Stakeholder
For Clinicians: Level 1 recommendations should be offered to most patients without extensive discussion, while Level 2 recommendations require exploring patient preferences and values through shared decision-making 1
For Patients: Level 1 recommendations mean most people in your situation would want this intervention and only a small proportion would not; Level 2 recommendations mean the majority of people would want the intervention but many would not, requiring careful consideration of personal values 1
For Policy Makers: Level 1 recommendations can be adopted as policy in most situations with minimal debate; Level 2 recommendations require substantial stakeholder involvement and may vary between regions 1