Apps

🧪 This platform is in early beta. Features may change and you might encounter bugs. We appreciate your patience!

Relative vs. Absolute Risk Confusion

Also Known As: Relative Risk Fallacy Risk Magnification Bias
Statistical Error ID: relative_risk_confusion

Definition

This error occurs when relative risk changes (percentages of percentages) are confused with or substituted for absolute risk changes, making effects appear much larger or smaller than they actually are. It is arguably the single most exploited statistical confusion in health journalism, pharmaceutical marketing, and policy debates.

Examples

A pharmaceutical company advertises that its drug 'cuts heart attack risk by 36%.' The actual numbers: in the control group 4.5% had heart attacks; in the treatment group 2.9% did. The absolute reduction is 1.6 percentage points — you need to treat about 63 patients for one year to prevent one heart attack. Both numbers are true; only one is featured.

A news headline reads: 'Eating bacon every day doubles your risk of colorectal cancer!' The baseline risk for an average person is about 4.5%. 'Doubled' means roughly 9%. The relative risk increase (100%) sounds catastrophic; the absolute increase (4.5 percentage points) is real but contextualised differently.

A workplace safety intervention is credited with 'reducing accidents by 50%.' Before: 2 accidents per 1,000 worker-years. After: 1 accident per 1,000 worker-years. The relative reduction is genuine, but the absolute reduction (1 fewer accident per 1,000 workers) helps a manager decide whether the cost of the intervention is proportionate.

Verification Steps
Verification Steps
Binary yes/no questions that an AI must answer to detect a reasoning pattern in a text.
Each of the 452 aspects has verification steps — simple yes/no questions designed to systematically detect whether a pattern appears in a text. For ad hominem: "Does the argument attack a person rather than their claim?" For false dichotomy: "Are only two options presented when more exist?" This ensures consistent, reproducible analysis.

Binary (yes/no) questions an LLM must answer to identify this aspect: