What is a posttest-only experimental design?

What is a posttest-only experimental design?

Entry. Subject Index Entry. The posttest-only control group design is a research design in which there are at least two groups, one of which does not receive a treatment or intervention, and data are collected on the outcome measure after the treatment or intervention.

What research design considers non random assignment of participants to groups?

Quasi-experimental research involves the manipulation of an independent variable without the random assignment of participants to conditions or orders of conditions. Among the important types are nonequivalent groups designs, pretest-posttest, and interrupted time-series designs.

When participants are not randomly assigned to conditions researchers?

The prefix quasi means “resembling.” Thus quasi-experimental research is research that resembles experimental research but is not true experimental research. Although the independent variable is manipulated, participants are not randomly assigned to conditions or orders of conditions (Cook & Campbell, 1979).

What is a pretest posttest design?

A pretest–posttest design is a form of pre-experimental design that does not have control or comparison groups. This is a major difference between pretest–posttest designs and processes such as quasi-experimental designs and randomized controlled trials.

Which of the following is a possible disadvantage of pretest-posttest research designs?

The only disadvantage of the pretest-posttest control group design compared to the posttest only design, is that there can be a threat to internal validity called the testing threat. As was discussed in an earlier chapter, this threat can occur when there is an interaction between the pretest and the treatment.

Why is pre-test and post-test necessary?

Pre and post tests are designed to measure your students’ growth in knowledge of a particular topic. Pre and posts tests not only assist in measuring how your students have improved, but they can also be a valuable diagnostic tool for more effective teaching as well!

What is the meaning of posttest?

: a test given to students after completion of an instructional program or segment and often used in conjunction with a pretest to measure their achievement and the effectiveness of the program.

Can a pretest-posttest design be controlled for?

But they can be controlled for using some of the methods described in Chapter 5. In a basic pretest-posttest design with switching replication, the first group receives a treatment and the second group receives the same treatment a little bit later on (while the initial group continues to receive the treatment).

How to improve on the posttest only nonequivalent groups design?

Another way to improve upon the posttest only nonequivalent groups design is to add a pretest. In the pretest-posttest nonequivalent groups design t here is a treatment group that is given a pretest, receives a treatment, and then is given a posttest.

When did the posttest only control group design start?

In 1993, Topf and Davis used a posttest-only control group design to examine if CCU (Critical Care Unit) noise affects REM (Rapid Eye Movement) sleep. So they randomly assigned 70 women with no hearing or sleeping problems to attempt to sleep in one of the following conditions:

Why are pretest designs poor at guarding against Assignment bias?

It is very poor at guarding against assignment bias, because the researcher knows nothing about the individual differences within the control group and how they may have affected the outcome. Even with randomization of the initial groups, this failure to address assignment bias means that the statistical power is weak.