Correlation vs. Causation
Definition
Correlation describes a statistical relationship between two variables that tend to change together. Causation means that one variable directly produces a change in another.
Correct Scientific Usage
Researchers distinguish correlation from causation by using controlled experiments, randomization, and repeated evidence. Observational studies can identify correlations, but causal conclusions require stronger designs and mechanistic support.
Common Misunderstandings
A common error is assuming that because two things are associated, one must cause the other. Many correlations arise from shared underlying factors or coincidence rather than direct cause.
Why It Matters
Mistaking correlation for causation can lead to incorrect conclusions, ineffective treatments, and misleading health claims. Understanding the difference is foundational to interpreting scientific evidence responsibly.
References
- Basic Introduction to Statistics in Medicine, Surgical Infections
- Correlation vs. causation, Association of Health Care Journalists
Related Terms
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