Association can be measured by all of the following except
**Core Concept**
Association between variables in statistics is a measure of how strongly one variable is related to another. In the context of medical research, association is often used to identify potential risk factors or correlations between different health outcomes.
**Why the Correct Answer is Right**
Association can be measured using various statistical methods, including correlation coefficient (e.g., Pearson's r), regression analysis, and contingency tables. These methods help researchers to quantify the strength and direction of the relationship between two variables.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is not a method used to measure association.
**Option B:** This option is incorrect because it is a measure of correlation, but not the only method used to measure association.
**Option C:** This option is incorrect because it is a measure of causality, not association.
**Clinical Pearl / High-Yield Fact**
When interpreting associations in medical research, it's essential to consider confounding variables, which can distort the relationship between variables. Adjusting for confounders using techniques like regression analysis can help to isolate the true association.
**Correct Answer: D. Causality**