Table 4Treatment 1 vs. Treatment 2: Numbers of studies and subjects, strength-of-evidence domains, magnitude of effect, and strength of evidence for key outcomes

Number of studies; subjectsDomains pertaining to strength of evidenceMagnitude of effect and strength of evidence
Risk of bias:ConsistencyDirectnessPrecisionAbsolute risk difference per 100 patients
MortalityInsufficient SOE
1;80RCT/MediumUnknownDirectImprecise−1 (95% CI −4 to +3)
14;384Retrospective cohort/MediumInconsistentDirectImprecise−7 to +5 (range)
Myocardial infarctionLow SOE
7: 625Retrospective cohort/HighConsistentDirectPrecise−3 (95% CI −5 to −1)
Severe diarrheaModerate SOE
4; 256RCTs/MediumConsistentDirectImprecise−4 (95% CI −8 to +1)
14; 28,400Cohort/MediumConsistentDirectPrecise−5 (95% CI −8 to −2)
Improved quality of lifeHigh SOE
6; 265RCTs/LowConsistentDirectPrecise−5 (95% CI −1 to −7)
Ulcer healingHigh SOE
6; 265RCTs/LowConsistentDirectPrecise+12 (95% CI +4 to +27)
5; 684Retrospective cohort/LowConsistentDirectPrecise+17 (95% CI +12 to +22)

CI, confidence interval; RCT, randomized controlled trial; SOE, strength of evidence.

From: Grading the Strength of a Body of Evidence When Comparing Medical Interventions

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