The first step in conducting a major literature review project is, of course, planning. To minimize bias - and to manage the workload projects like these entail - systematic reviews necessarily involve more than one person. So start by assembling a strong team.
You and your team will need to develop a good research question, determine the type of review you will conduct (systematic, scoping, rapid, etc.), and establish the inclusion and exclusion criteria (e.g., you're only going to look at studies that use a certain methodology). All of this information needs to be included in your protocol (see below).
You will also need to ensure that the project is viable. Are you certain there is enough literature on your area of focus to warrant a review? Also, if others have already published a review on this same question fairly recently, you'll need to reconsider yours. Do some test searches in a few key subject databases for relevant literature and check the various protocol registries to see if a similar review is already planned.
Using a tool like Covidence - which was specifically designed for systematic reviews - can help you manage a review project from start to finish. Head over to the Covidence tab/page of this guide to learn more about it.
Systematic reviews require specific, focused, and well-formulated research questions. In the health sciences, researchers often use the PICO format to generate research questions. PICO stands for:
It's okay if your question does not fit neatly into the PICO format. (Many lines of inquiry may not have a definable C, for instance.) However, you might find that you'd be better served by another framework, especially if you are investigating a social sciences topic or focusing on certain types of qualitative or policy-based research. For example, another well-known option is the SPIDER (Sample, Phenomenon of Interest, Design, Evaluation, research type) framework.
A protocol is essentially an "intent to pursue." It's a document outlining the what and how of your proposed systematic review. According to PRISMA's page on protocols, this document "describes the rationale, hypothesis, and planned methods of the review. It should be prepared before a review is started and used as a guide to carry out the review."
Your protocol should be made publicly available and registered in a registry. PROSPERO is the registry of choice for the health sciences. The Open Science Framework (OSF) is a good option for those conducting non-clinical systematic reviews.
If you plan on conducting a systematic or scoping review, it's a good idea to become familiar with the established best practices for doing so. These guidelines, handbooks, and standards were developed by reputable organizations that support and advocate for evidence-based medicine, including the publication of evidence syntheses.
