What is a longitudinal design?
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A longitudinal design is a quasi-experiment design in which a researcher measures a particular groupd of people for a long period of time. It can also be defined as a correlation research study in which there are many observations being conducted over long periods of time on the same group, or number, of people. Many times, longitudinal studies are conducted to measure trends over a particular life-span of an individual. Usually the same people are studied in longitudinal studies so that the accuracy of the results are the greatest. Also, by using the same people, it is less likely that those people are going to be a part of the result in cultural differences across many different generations. Longitudinal studies are also commonly used in the medical field because they help to measure medicine and discover certain diseases.
Example / Application
Example: - Gender and Gender Role Attitudes
Application: The topic of this article requires to have a longitudinal study completed. The author gives the reasoning that it is because gender orientation and earnings are two variables that fluctuate over time. These two variables were the basis of his study. So it makes sense that he would choose to conduct a study that correlates with long-term observations.
Judge, T. A. & Livingston, B. A. (2008) Is the Gap More Than Gender? A Longitudinal Analysis of Gender, Gender Role Orientation, and Earnings Journal of Applied Psychology Vol. 93, No. 5, 994–1012
Heiman, G. W., (2002). Research Methods in Psychology. 3rd Edition. Boston & New York. Houghton Mifflin Company.