Nursing Research Q40
What is a characteristic of an independent variable?
A. It is the variable that is predicted to change.
B. It varies with a change in the dependent variable.
C. It is manipulated by the researcher.
D. It can be identified only by changes in the dependent variable.
Correct Answer: C. It is manipulated by the researcher.
The independent variable is manipulated by the researcher and has a presumed effect on the dependent variable. They are either manipulated by the researcher or are observed by the researcher so that their values can be related to that of the dependent variable. For example, in a research study on the relationship between mosquitoes and mosquito bites, the number of mosquitoes per acre of ground would be an independent variable” (Jaeger, 1990, p. 373).
Option A: It is the dependent variable that is predicted to change. The dependent variable is the outcome. In an experiment, it may be what was caused or what changed as a result of the study. In a comparison of groups, it is what they differ on.
Option B: The independent variable is presumed to change the dependent variable. In a research study, independent variables are antecedent conditions that are presumed to affect a dependent variable.
Option D: The independent variable is manipulated by the researcher and is identified at the beginning of the study. While the independent variable is often manipulated by the researcher, it can also be a classification where subjects are assigned to groups. In a study where one variable causes the other, the independent variable is the cause. In a study where groups are being compared, the independent variable is the group classification.