In an ecological study, countries with higher fat intake show higher rates of breast cancer. A researcher concludes that dietary fat causes breast cancer. The specific logical flaw in this conclusion is termed:

• A Simpson's paradox
• B Confounding by indication
• C Effect modification
• D Ecological fallacy (atomistic fallacy) ✓

Explanation

The ecological fallacy (also called the ecological fallacy or atomistic fallacy in reverse) refers to incorrectly inferring individual-level associations from group-level data. A country with high average fat intake may include many non-consumers; the aggregate correlation does not prove individual exposure–disease links. Simpson's paradox refers to a reversal of association when data are combined across strata. Confounding by indication is a pharmacoepidemiology concept. Effect modification is when the effect of an exposure varies across subgroups.

Reference: Park's Textbook of Preventive and Social Medicine, 27th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.