Table 2Strength of evidence grades and definitions

GradeDefinition
HighHigh confidence that the evidence reflects the true effect. Further research is very unlikely to change our confidence in the estimate of effect.
ModerateModerate confidence that the evidence reflects the true effect. Further research may change our confidence in the estimate of effect and may change the estimate.
LowLow confidence that the evidence reflects the true effect. Further research is likely to change our confidence in the estimate of effect and is likely to change the estimate.
Insufficient Evidence either is unavailable or does not permit estimation of an effect.

Source: Owens et al., 200931

From: 2, Methods

Cover of Enhancing the Use and Quality of Colorectal Cancer Screening
Enhancing the Use and Quality of Colorectal Cancer Screening.
Evidence Reports/Technology Assessments, No. 190.
Holden DJ, Harris R, Porterfield DS, et al.

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