cause-and-effect relationship.  

cause-and-effect relationship.  

1-Experimental research involves a variable that can be manipulated. With this type of experiment, participants can be randomly assigned to either the control group or treatment group. It often demonstrate a cause-and-effect relationship.

On the contrary, nonexperimental research involves a variable that cannot be manipulated or change. The variable is controlled and has to remain constant. Participants will not be randomly assigned to either the control or treatment group. This type of experiment does not demonstrate a true cause-and-effect relationship but instead, relies on observation and correlation.

For instance, in 2013, New England Journal of Medicine released an article on what was believed to have been an experimental study. The article suggested that Mediterranean diet lowers the chance of heart attack, stroke, and other cardiovascular diseases by 30%. Mediterranean diet has been recommended since for general prevention. However, it was retracted in 2018 after it was reported that 14% of the participants were not randomly assigned to either a control or treatment group. Married couples were put into the same group and even participants from an entire village was placed into a single group. All this was never reported in the paper.

References:

Yu, C. (2018). Experiment and Non-experiment. Retrieved from http://www.creative-wisdom.com/teaching/WBI/doe.shtml

Bonds-Raacke, J.M., & Raacke, J.D. (2014). Nonexperimental Research Methods from Research Methods: Are You Equipped?.Retrieved from https://he.kendallhunt.com/sites/default/files/uploadedFiles/Kendall_Hunt/Content/Higher_Education/Uploads/Bonds_Raacke_Research_2e_Ch4.pdf

 

 

2-Experimental research is when the researcher manipulates or controls the independent variable. Experimental research normally is used when the researcher has a specific question or hypothesis (Price et al, 2017). This is done to identify a cause and effect relationship, normally conducted with an experimental group and placebo or non-manipulated group. An example of this is to determine effects of certain medications such as pain relievers. Half of the group will receive a pain pill to manage their pain symptoms while the other half will receive a placebo pill. The expected results should be that the half who received the placebo pills did not experience pain relief.