PRISMA stands for Preferred Reporting Items for Systematic Reviews and Meta-Analyses. It is an evidence-based minimum set of items for reporting in systematic reviews and meta-analyses.
The flow diagram is part of the reporting standards of PRISMA and is comprised of a four-phase diagram (Identifying, Screening, Eligibility, and Finalizing). It depicts the flow of information through the different phases of a systematic review. It maps out the number of records identified, included and excluded, and the reasons for exclusions.
Different templates are available depending on the type of review (new or updated) and sources used to identify studies.
In this section:
In this portion of the diagram the total search yields and deduplication totals are recorded. This is obtained searching database(s) or other sources on a specific date, run all your searches, and record the number.
Results should be exported and then imported into to a citation manager or screening tool (if one is being used) Only through this process can total results and especially duplicates be quickly removed and identified. Duplicates appear if two or more sources are searched; single source searches result in zero duplicates.
Note: The * allows for individual search yields by source to also be listed rather than a total sum only. This is recommended if totals were documented at an individual source level
In this section:
Records screened and excluded come from the title/abstract portion of screening, often referred to as 'Phase 1'. This is making a decision on what to include or exclude based solely on relevance to the research question. This phase is not looking at the full text, study quality and/or strength, etc.
Reports Sought for Retrieval is another way of saying those that were retrieved for full text and is often referred to as 'Phase 2'. Those not retrieved could be ones not accessible.
Reports assessed for eligibility is the total of those retrieved minus those not retrieved.
Lastly, reports excluded are those that have been read through but they don't meet the criteria to be included. Reasons for exclusion are to be documented here as well.
In this section:
This box contains those reports (articles) that have made it through the entire screening process and the number of studies entailed. This number could be equivalent but could differ if multiple publications use data from the same population. This number typically is small (even single digits) but is dependent on the total yield and other factors.
