Evidence and statistics
7 of 142 calculators
- OR / RROdds ratio, relative risk, and risk differenceEffect sizes with 95% confidence intervals from a 2 × 2 table.
- NNTNumber needed to treatARR, RRR, relative risk, and NNT (or NNH) from event rates.
- OR → RRConvert odds ratio to risk ratio (Zhang-Yu)Approximates a risk ratio from an adjusted odds ratio and the control-group risk.
- Sens/SpecDiagnostic test statistics (2 × 2)Sensitivity, specificity, predictive values, and likelihood ratios from a 2 × 2 table.
- FragilityFragility indexHow many patients' outcomes would need to change for a significant trial result to lose significance.
- Sample sizeSample size for comparing two groupsParticipants needed per group for two proportions or two means.
- PowerStatistical power for two proportionsPower of a completed or planned two-group comparison of proportions.
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