Table 2.

Classification of recommendations⁴

A	At least one meta-analysis, systematic review or RCT rated as 1++, and directly applicable to the target population; or A body of evidence consisting principally of studies rated as 1+, directly applicable to the target population, and demonstrating overall consistency of results
B	A body of evidence including studies rated as 2++, directly applicable to the target population, and demonstrating overall consistency of results; or Extrapolated evidence from studies rated as 1++ or 1+
C	A body of evidence including studies rated as 2+, directly applicable to the target population and demonstrating overall consistency of results; or Extrapolated evidence from studies rated as 2++
D	Evidence level 3 or 4; or Extrapolated evidence from studies rated as 2+
Good Practice Points IP	Recommended best practice based on the clinical experience of the Guideline Development Advisory Group and patient preference and experience Recommendation from NICE Interventional Procedures guidance

RCT, randomised controlled trial; NICE, National Institute for Health and Clinical Excellence.