high confidence in the effect estimate, high quality of the evidence, high strength of the evidence
High certainty of the evidence means that the likelihood is low that the effect will be different enough from what the research found that it might affect a decision.
Judgements about the certainty of the evidence are based on factors that reduce the certainty (risk of bias, inconsistency, indirectness, imprecision, and reporting bias), and factors that increase the certainty, such as dramatic treatment effects.
There is high certainty of the evidence when there are few or no factors that reduce the certainty of the evidence, or when there are factors, such as dramatic treatment effects, that increase the certainty of the evidence.
If you feel that this definition hasn't helped you to understand the term, click on our monkey to let us know.