A variable which on the basis of a previously established relationship with a dependent variable, may be used for the solution of specific values of the dependent variable.
In epidemiology, a characteristic being considered or tested for its relationship to a health condition.
In epidemiology and research, the agent that incites a response; the stimulus (e.g., the dose part of a dose-response curve). In the smoking and heart disease study cited in the entry called dependent variable, smoking would be the independent variable.
The variable that is manipulated in an experimental study.