Before you start your review, explore existing reviews. You don't have to reinvent the wheel.
Look to existing reviews as guides that can:
Is there another systematic review that has already been published on your topic? If so, there may still be a reason for you to write your own, such as:
Tips when searching for systematic reviews related to your topic:
This guide was adapted from Systematic Reviews by University of Texas Libraries (https://guides.lib.utexas.edu/systematicreviews) which is licensed under a Creative Commons Attribution-NonCommercial 2.0 Generic License.