FullCalculator

Odds Ratio Calculator

2x2 Table

Formula

OR = (a*d)/(b*c). 95% CI = exp(ln(OR) +/- 1.96*SE)

Frequently Asked Questions

What is an odds ratio?
The odds ratio measures association between exposure and outcome. OR > 1 suggests increased odds, OR < 1 decreased odds, OR = 1 no association.

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