Quasi-Experimental Designs, Term Paper Example

The quasi-experimental research design involves several key elements similar to experimental studies. A quasi-experimental study implements an intervention to study the effects on a specified problem (Shaugnessy, Zechmeister, &Zechmeister, 2008).  The quasi-experimental design also includes a comparison between the intervention group and the control group.  However, the quasi-experimental study does not have the same level of control as experimental studies: In particular, the quasi-experimental study lacks random assignment and other mechanisms meant to prevent confounding (Goodwin, 2009).

The hypothetical quasi-experiment will focus on how a class on stress and depression management influences college students’ overall level of stress. The quasi-experiment will focus on a class of finance majors at a small liberal arts college in New York: Since the students take the same classes, one-half of the class will have a weekly stress management class throughout the semester; the other half of the class will not have a class but just a required meeting for majors.  The principal investigator will then have the students take a test at the beginning of the semester measuring their stress levels, once in the middle of the semester, and one at the end of the semester to measure progress. The dependent variable will be the student’s stress level; the independent variable will be exposure to stress management therapy in addition to other variables to help control for confounding such as total credits taken and participation in extra credit activities.  This study could be turned into an experimental one if the participants were randomly assigned to the groups.

Another potential quasi-experimental study could explore the impact of nutritional information on a student’s diet.  A group of students at a liberal arts school would be placed into two different groups: 1) A weekly discussion group on how to improve nutritional habits; 2) A weekly discussion group on discussing class-based topics.  The students would also participate in a survey writing down what they ate every week-the investigators would then measure whether the group that attended nutritional sessions had changed their eating habits compared to those who didn’t attend the sessions.  The main threats to internal validity in this project would likely be: history, testing, selection, and subject mortality.  College students are exposed to many different factors that might impact their nutritional habits including economic limitations and other influences encountered at college (including friends).  Testing would be a concern due to the constant writing down of meal selection: the very act of keeping track of such information may lead individuals to change their behavior.  Regarding subject mortality, college students notoriously do not attend class and may drop out of participation in the weekly nutrition sessions and counseling.  The final internal threat to validity involved in the study would be selection: Some students may have better nutritional habits at the beginning than other students.

References

Shaugnessy, J., Zechmeister, E., &Zechmeister J. (2008).  Research Methods in Psychology. New York: Mcgraw Hill.

Goodwin, J.C. (2009).  Research in Psychology: Methods and Design.  New York, Wiley.