In a literature review, the important unit is the relationship between a claim and the source supporting it. Paste a paragraph that keeps those together. Include the sentence explaining whether two studies agree, differ or address different populations. Without that context, a language edit can make a careful comparison sound like a contradiction.
Use the scan findings as places to reread, not a checklist of words to eliminate. If several sentences repeat that the literature is complex, state the specific disagreement instead. Name the method, sample or definition that creates it, using only information you have checked in the original studies.