Could someone please help me how to do meta-analysis of categorical variables? I know Odds-ratio is common method but i was just not sure about it. So here are the conditions I have.
3 to 4 categorical variables (control, light, medium, heavy)
I have response variable in increased or decreased (two levels). Because the response I get is not in numbers. For example: "medium level increased the microbial community diversity or heavy level decreased the microbial community diversity"
Any help or reference to a nice book/guide would be highly appreciated.