FAQs for Systematic and Scoping Reviews

A duplicative review refers to a review that replicates or overlaps with the research question of an existing review.

Read the following article to learn more about factors to consider when addressing duplicative or possible duplicative reviews:

Garner, Paul, et al. “When and How to Update Systematic Reviews: Consensus and Checklist.” BMJ (Online), vol. 354, 2016, pp. i3507–i3507, https://doi.org/10.1136/bmj.i3507.

Consider searching key databases related to your topic and repositories for protocols such as PROSPERO, Open Science Framework (OSF), and Feinberg’s Prism.

Systematic reviews often take two or more years to complete. Consequently, there may be ongoing reviews not yet published but documented as protocols.

Here are strategies you can employ after discovering a published review or protocol that overlaps with your team's review question:

• Contact the other team: Reach out to gather information about the status of their review. Some teams may abandon reviews without completing or updating their online protocol, while others might be actively working on their project.
• Refine your research question: Introduce unique element(s) that distinguish your review from the existing one. 
• Explore collaboration: If you are committed to a question that overlaps with existing or planned reviews, consider reaching out to teams working on related projects. Collaborating on a review can enhance the quality and impact of the research while avoiding redundancy.

Here are several reasons to avoid duplicative reviews:

• Redundancy: An existing review already addresses the research question. Most duplicative reviews do not contribute new insights into a research topic.
• Resource intensive: Reviews are time and resource-intensive projects. Duplicative reviews require the same efforts as original reviews without often adding new insights or significantly updating the evidence.
• Negative impact: Duplicating a review may negatively impact the original review, as it generally takes a few years for articles that cite the original review to be published. That metric helps readers and reviewers understand the true impact of the study.
• Publication challenges: The review may be rejected for publication, as journals generally prioritize original studies that fill gaps in the literature or offer new perspectives on existing evidence. Reputable journals often seek novel studies that address unique research questions.

Galter Library provides full collaborative support to teams working on unique reviews. We recognize the significant time and resources invested in developing and publishing a systematic review and allow the team who first presents the question the opportunity to complete and publish their review. We extend this professional courtesy to all reviewers (NU and non-NU) and expect the same consideration from other teams.