Redundant or poorly organised reviews waste effort and resources, and add to decision making confusion.
Good planning improves review quality and reduces stress later in the process.
Article - Disorganized Systematic Reviews and Meta-analyses: Time to Systematize the Conduct and Publication of These Study Overviews? The American Journal Of Medicine, 2016.
Article - Replication, Duplication, and Waste in a Quarter Million Systematic Reviews and Meta-Analyses. Circulation: Cardiovascular Quality and Outcomes. 2018
A scoping review can be a useful prior stage to a full systematic review. Scoping reviews aim to provide an overview of the literature around a topic. They are typically more broad, but with less depth than a systematic review, and generally do not include any statistical analysis. They can be useful for identifying questions which are suitable for a systematic review.
Systematic reviews are significant undertakings requiring more than a single individual's input. Typically a systematic review team will consist of:
Note. If you are considering undertaking a review as an individual then it is more appropriate to describe your study as a review done in a systematic manner, than a systematic review per se. The same processes should be followed, as all research benefits from a systematic method, but a single researcher cannot eliminate bias from the review process, so cannot meet the standards of a systematic review.
You should have a clear idea on what you are question is. You need to do this before starting to search the literature in earnest so you do not waste time and effort on unnecessary material.
Discuss with your team or supervisor what exactly you are asking and what the criteria for inclusion and exclusion are.
You might want to use the PICO framework to help form your question.
If you are unsure, consider allowing time for a scoping review to establish the research 'landscape'. This can help clarify where to direct your efforts.
By the end of the planning stage you should have a protocol for your review. Writing up a protocol clarifies your intentions, provides a reference for team members and helps make sure you are well prepared for your study. It is a good idea to register your protocol at PROSPERO so other researchers do not inadvertently duplicate your study.