PRISMA 2020 Checklist: A Practical Walkthrough

PRISMA 2020 is often misunderstood as a methodology standard. It isn't -- it's a reporting checklist, 27 items covering what a systematic review needs to disclose so a reader can judge its quality and reproduce its process. You can run excellent methodology and still fail a PRISMA check by simply not writing it down clearly enough.

Title and abstract

PRISMA requires the title to identify the report as a systematic review -- not "A Review of X," but explicitly "A Systematic Review of X." The abstract needs a structured summary covering objectives, eligibility criteria, information sources, risk of bias assessment, synthesis methods, and main results.

Introduction and rationale

State clearly what is already known and what gap this review fills. A rationale that could apply to any review on the topic -- rather than explaining specifically why this review, now -- reads as weak justification to reviewers.

Methods: the section that gets the most scrutiny

This is where most of the 27 items live. PRISMA wants explicit reporting of: eligibility criteria, information sources and the date each was last searched, the full search strategy for at least one database, the selection process and how many reviewers were involved, the data collection process, the specific outcome and effect measures used, and the methods used to assess risk of bias and certainty of evidence.

Results: the flow diagram is not optional

The PRISMA flow diagram -- showing records identified, duplicates removed, records screened, full texts assessed, and studies ultimately included, with reasons for exclusion at each stage -- is one of the most-checked items in the entire checklist. The counts at each stage should add up cleanly; if they don't, that inconsistency will be the first thing a careful reviewer catches.

Discussion and other information

Limitations need to be discussed at both the individual-study level and the review level. PRISMA also requires disclosure of registration and protocol availability, funding sources, and competing interests.

The most common ways reviews fail this checklist

In practice, the same handful of gaps show up repeatedly: search strategies reported for only one database when multiple were used, missing or inconsistent flow diagram numbers, risk-of-bias methods described too vaguely to apply the same way twice, and discussion sections that summarize findings without genuinely engaging with the review's own limitations.

Treating PRISMA as a drafting checklist -- reviewed line by line before submission, not after a rejection -- is the difference between a smooth review process and repeated rounds of "please clarify" from journal editors.