When might you use the posttest-only design? The
advantage would be that without a pretest you wouldn’t be taking as much time
. The disadvantage would be the useful-side of the pretest where you can see changes as well as attrition effects.
What is a posttest only design?
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.
Which of the following is an advantage of using a pretest-posttest design?
tell the participants what is being studied and why. Which of the following is an advantage of using a pretest-posttest design over using a posttest-only design?
It confirms whether the groups are equivalent.
When would you use a posttest only design?
Feasible with fewer resources than most designs: The one-group posttest-only design is especially useful
when the intervention must be quickly introduced
and we do not have enough time to take pre-intervention measurements.
What is a disadvantage of pretest-posttest design?
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.
What are two advantages to a posttest only design?
The key threats to this design are history and maturation. When might you use the posttest-only design? The advantage would be
that without a pretest you wouldn’t be taking as much time
. The disadvantage would be the useful-side of the pretest where you can see changes as well as attrition effects.
What is the difference between a posttest only design and a pretest posttest design?
Pretest–posttest designs are
employed in both experimental and quasi-experimental research
and can be used with or without control groups. For example, quasi-experimental pretest–posttest designs may or may not include control groups, whereas experimental pretest–posttest designs must include control groups.
What is a one shot case study design?
A
type of pre-experimental design where a single group of test units is exposed to an experimental treatment and a single measurement is taken afterwards
. It only measures the post-test results and does not use a control group.
What is the major weakness of the single group posttest only design?
Whilst this posttest only design does find many uses, it is limited in scope and contains many threats to validity. 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.
How do you identify a quasi experimental design?
Like a true experiment, a quasi-experimental design aims to establish a cause-and-effect relationship between an independent and dependent variable. However, unlike a true experiment, a quasi-experiment does not rely on random assignment. Instead,
subjects are assigned to groups based on non-random criteria
.
What are the limitations of experimental designs?
Limitation:
They may be more expensive and time consuming than lab experiments
. Limitation: There is no control over extraneous variables that might bias the results. This makes it difficult for another researcher to replicate the study in exactly the same way.
What are the disadvantages of a control group?
Failure to use a control group, or use of an inappropriate control group, can make it impossible to draw meaningful conclusions from a study.
Failure to Demonstrate the Comparability of Patients in Treatment and Control Groups
.
What is a disadvantage of using the strongest manipulation possible in a research?
What is a disadvantage of using the strongest manipulation possible in a research?
It creates a situation different from a real-world situation
.
What is the purpose of a posttest?
What is the purpose of Posttests? Postests are
used to determine exactly which treatment conditions are SIGNIFICANTLY DIFFERENT.
What are the biggest threats to the validity of this method?
History, maturation, selection, mortality and interaction of selection and the experimental variable
are all threats to the internal validity of this design.
What is the difference between pre test and post test?
Typically, a pretest is given to students at the beginning of a course to determine their initial understanding of the measures stated in the learning objectives, and
posttest is conducted just after completion of the course
to determine what the students have learned.
