Risk Ratio and Difference
Compare observed event proportions between groups.
Your numbers
Risk ratio
Association does not establish causation. A zero reference proportion makes the ratio undefined.
Scenario comparison
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Formula
Use RR = (a/n)/(b/m) and D = a/n−b/m. a and b are event counts for groups A and B; n and m are their totals. D is the probability difference, displayed in percentage points.
Compare observed event proportions between groups.
Worked example
- A events
- 20
- A total
- 100
- B events
- 10
- B total
- 100
- Risk ratio
- 2
- Absolute difference
- 10 percentage points
- A event proportion
- 20 %
- B event proportion
- 10 %
Scope and limitations
Association does not establish causation. A zero reference proportion makes the ratio undefined.
Inputs are checked for missing values and allowed ranges. A result outside the finite numeric range is not displayed. Rounding affects display, while the calculation uses the model’s numeric precision.
Check your units and assumptions before relying on a result. Changing a label does not convert a currency or physical unit.
Formula version: d24faa6fc634 · Example checked: