The PROSPERO Registry is an international online database designed for the prospective registration of Systematic Review and Meta-Analysis protocols. It is managed by the Centre for Reviews and Dissemination (CRD), University of York and is widely recognized as one of the major standards in evidence-based research. The main objective of PROSPERO is to improve transparency and methodological quality by documenting the planned review methods before researchers begin full data extraction or statistical analysis. Registering a protocol helps reduce unnecessary duplication between research groups and decreases the risk of selective reporting or changing outcomes after seeing the results.

PROSPERO is mainly intended for:

• Systematic Reviews,
• Meta-Analyses,
• and evidence synthesis projects related to health and medical outcomes.

It is commonly used in reviews involving:

• therapeutic interventions,
• diagnostic methods,
• prognostic studies,
• epidemiological research,
• and public health topics.

In contrast, PROSPERO is generally not designed for:

• narrative reviews,
• simple literature reviews,
• scoping reviews without outcome evaluation,
• case reports,
• or individual original clinical studies.

Although PROSPERO registration is not absolutely mandatory for every Systematic Review, many high-quality journals strongly recommend or require prospective registration before submission. Protocol registration increases the scientific credibility of the review because it demonstrates that the methodology, objectives, eligibility criteria, and statistical plans were predefined before the final results became known. Researchers usually mention the registration number in the manuscript using a statement such as:

“This Systematic Review and Meta-Analysis was prospectively registered in PROSPERO (CRD4202…7890).”

This statement is commonly inserted in the: