In the current study, there are three treatment groups that undergo stress relief management techniques. Experts utilize various strategies to measure one’s anxiety, including evaluation of heart rate variability, brainwaves, and hormones (Bhanote, 2022). However, these approaches require significant funding, which is why it is plausible to use a self-assessment questionnaire, such as the Perceived Stress Scale (PSS) (Bhanote, 2022). The PSS is an affordable and relatively accurate method to evaluate one’s anxiety levels, which makes it appropriate for the current study to study the differences between the treatment groups.
Considering the experiment design, all participants will complete the self-assessment questionnaire two times – before and after the treatment. The experts will calculate the average score for each group, which will be the quantitative outcome variable. Comparing the initial evaluation with the results will allow researchers to make definitive conclusions about the effectiveness of the approaches and estimate primary differences. The main problem regarding internal validity is the lack of a control group. In other words, it is difficult to understand whether the differences between treatment groups emerge from applied techniques or the general environment. Therefore, it is appropriate to introduce the fourth group in the study, which will serve as the control sample and not undergo treatment. The main problem with external validity is that teams are formed from a homogenous population (students or clients at an agency), meaning that they share common characteristics. As a result, it is impossible to generalize the results based on the experiment due to its limited selection of people.
I believe that ANOVA is an appropriate statistical test for the current experiment. Namely, the study compares more than two groups, meaning that neither regression tests nor paired/independent t-tests are appropriate (Bevans, 2020). Moreover, the predictor variable is categorical (the type of stress relief technique), while the outcome variable is quantitative (metrics on self-assessment tests). According to the chart by Bevans (2020), these conditions only apply to the ANOVA statistical method. Ultimately, I believe it is reasonable to use the PSS method to measure the outcomes, introduce the fourth group to mitigate internal validity concerns, and use ANOVA for analysis.
References
Bevans, R. (2020). Choosing the right statistical test | Types & examples. Scribbr. Web.
Bhanote, M. (2022). How can you measure stress? Healthline. Web.