Author Question: A researcher wants to know whether a new drug reduces anxiety. Forty participants who suffer from ... (Read 119 times)

eruditmonkey@yahoo.com · **on:** Jun 19, 2018

A researcher wants to know whether a new drug reduces anxiety. Forty participants who suffer from anxiety disorder are assigned randomly to one of two groups. One group gets the new drug and the other group gets a placebo. Neither group knows which they receive. After 30 days on the drug, their anxiety levels are measured. In this experiment, is the independent variable and is the dependent variable.

a. anxiety, the new drug
b. the new drug, the placebo
c. anxiety, the placebo
d. the new drug, anxiety

Question 2

Identify the three types of nonequivalent control group designs discussed in the text noting possible advantages or disadvantages of each.

What will be an ideal response?

Athena23 · **Reply #1 on:** Jun 19, 2018

Answer to Question 1

D

Answer to Question 2

Posttest-only designs have no equivalent control group for comparison, and there are no pretest measures to establish the equivalency of groups. Pretest/posttest designs allow us to compare the groups on the pretest and posttest, and to compare within groups from pretest to posttest. However, because participants are not randomly assigned, we cannot say they are equivalent. Time-series designs allow us to see the effect of the treatment over time because many measures are taken. There is a nonequivalent control group available for comparison; however, because participants are not randomly assigned, we cannot say they are equivalent.