I am trying to do a systematic literature review where I will identify the best hybrid model regardless of the dataset. So I want to focus on the methodology in this review and not on the dataset. But can I compare different works that use different hybrid methods where the data in one work are rainfall and in the other are financial variables, using RMSE?
I am in the first stages of defining my research question and I want to define it properly so as not to get into a crossroad. So don't check all the databases and synthesize the works and then don't have the opportunity to compare the findings.