Ha ha I just Googled this myself. I shall include what I put into my review -
A critical review is an example of secondary research with no patient intervention involved. Therefore, no ethical approval was needed for this review; however, there are ethical considerations to be observed in all research. It is the reviewer's responsibility to make the research as subjective as possible and not let personal bias and opinion affect the study. Results need to be reported as accurately as possible, and, if they are of importance in contributing to the evidence base, the reviewer is obliged to publish them.
A critical review is an example of secondary research with no patient intervention involved. Therefore, no ethical approval was needed for this review; however, there are ethical considerations to be observed in all research. It is the reviewer's responsibility to make the research as subjective as possible and not let personal bias and opinion affect the study. Results need to be reported as accurately as possible, and, if they are of importance in contributing to the evidence base, the reviewer is obliged to publish them.