(Translated by https://www.hiragana.jp/)
EBM: Levels of Evidence - Essential Evidence Plus
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Levels of Evidence

Select an evidence rating scale to display detailed information.

Grading of Recommendations Assessment, Development and Evaluation (GRADE)

Code Quality of Evidence Definition
A High

Further research is very unlikely to change our confidence in the estimate of effect.

  • Several high-quality studies with consistent results
  • In special cases: one large, high-quality multi-centre trial
B Moderate

Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.

  • One high-quality study
  • Several studies with some limitations
C Low

Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.

  • One or more studies with severe limitations
D Very Low

Any estimate of effect is very uncertain.

  • Expert opinion
  • No direct research evidence
  • One or more studies with very severe limitations

Source: GRADE (Grading of Recommendations Assessment, Development and Evaluation) Working Group 2007 1 (modified by the EBM Guidelines Editorial Team)