Concept explainers
A researcher wants to describe the effectiveness of a new program (compared to the old program) for teaching reading to elementary school children. Describe how this study could be done as a posttest-only nonequivalent control group design. Next, describe how this study could be done as a nonexperimental pretest-posttest design.
How the above study can be conducted as a posttest-only nonequivalent control group design and nonexperimental pretest-posttest design.
Introduction:
A posttest-only nonequivalent control group design compares two nonequivalent groups of participants. One group is observed after receiving the treatment and the other group is measured at the same time but receives no treatment.
A nonexperimental pretest-posttest design compares two nonequivalent groups. One group is measured twice, once before and once after the treatment and the other group is measured at the same times but no treatment is given.
Answer to Problem 8E
Solution:
The post-test-only nonequivalent control group design and nonexperimental pretest-post-test design is possible and explained as follows.
Explanation of Solution
- For post-test only nonequivalent control group design: There are two groups taken, mostly two different sections from the same class of the elementary school children. One group is treated as per the new program and one group is treated as per the old program (control group). The results are examined after the completion of both the programs, and the results are compared. The groups are examined only after the treatment is complete.
- For nonexperimental pretest-post-test design: Here two groups are considered from the different sections of the elementary school. They are examined for factors like reading ability, IQ, interest in reading, etc. before the treatment is given. One group is then treated as per the new program and the other group (control group) is treated as per the old program. The results are compared with the study. The groups here are examined both before and after the treatment.
Conclusion:
The nonexperimental pretest-posttest design is a better approach to this study as it eliminates the threats to internal validity.
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