While conducting a controlled research study, the nurse wants greater assurance that the result is ...

ANS: D
In a controlled study, some of the participants are assigned to the treatment group, and others are assigned to the control group by a random process. The control group does not receive the treatment. In the clinical trial of a medication, the control group receives a placebo. The purpose of a control group is to prevent bias and ensure that the outcome results from the treatment rather than some other factor. An independent variable is a concept or idea whose value determines the value of other (dependent) variables. In research, the independent variable comprises the experimental treatment or intervention, and it is manipulated by the researcher to yield various outcomes. The dependent variable is the outcome that is affected by manipulation of the independent variable.