just compare two or more groups by observing the effect of independent variable on dependent variable. Like for example you want to observe the effects of stress on people, you group a randomized picked subjects into two (or more) then experiment on them like stress them, make them feel insecure etc. That's when you'll get the results and that's what causal comparative research is, am i right?lolol
or you can read some articles in google if u don;t quite understand my explanation(hehe)(๑•ㅂ•)و✧:
https://methods.sagepub.com/reference/encyc-of-research-design/n42.xml#:~:text=In%20causal%2Dcomparative%20research%2C%20the,effect%20on%20ACT%20test%20scores.
How do you do a casual comparative in your research???