Question

#1-4

1. True or False (circle one): Confounding and interaction are different concepts that may occur simultaneously. 2. True or False (circle one): If interaction exists on an additive scale, it also exists on a multiplicative scale. 3. True or False? Interaction is completely reciprocal, in that if Z modifies the effect of A, then A modifies the effect of Z. 4. True or False? Sample size inevitably decreases as more strata are created in subgroup analysis, making it less likely that heterogeneity would occur by chance alone. 5. Which of the following is correct about interaction/effect modification?

Answer 1

Ans) 1) True

Explaination:

- Confounding variable is a variable that correlates with both your regressor and the dependent variable. Interaction is much more complicated because it means that two separate regressors work together to create an outcome variable.

2) False

Explaination:

- Interaction on an additive scale means that the combined effect of two exposures is larger (or smaller) than the sum of the individual effects of the two exposures, whereas interaction on a multiplicative scale means that the combined effect is larger (or smaller) than the product of the individual effects.

3) True

Explaination:

- The word reciprocal means there is a mutual give and take between or among individuals or objects. So, taken together, reciprocal interaction refers to an exchange in which individuals or objects exhibit similar behavior, either at the same time or in a back-and-forth manner.

4) False

Explaination:

- improves the representation of particular strata (groups) within the population, as well as ensuring that these strata are not oover-represented.This will increase overall sample size required for the research, which can increase costs and time to carry out the research.