1What is evidence synthesis?
Evidence synthesis is a process of identifying, selecting, and combining multiple studies to inform practice and policy decisions around a topic or specific research question.
Watch a short video from Cochrane [Cochrane, 3 minutes] that explains what evidence synthesis is and why we need it.
What is Covidence?
Covidence is a web-based collaboration tool for performing evidence syntheses and literature reviews. Covidence is used to screen at both screening title abstract and full text stages, to collect the data from the included studies, and to assess risk of bias.
Covidence is free for NIH staff to use. At least one user must be from NIH to request access and use Covidence. Your evidence synthesis review team members from outside of NIH can also use Covidence.
If you are working with a NIH Librarian on your evidence synthesis, they will create the project in Covidence and provide information on maximizing its use.
Do I need to work with a librarian to use Covidence?
No, but if you are from NIH, we strongly encourage you to work with the NIH Library’s Evidence Synthesis Service on your review.
Learn more about Covidence:
Who can request evidence synthesis support via NIH Library?
Our services are available to any NIH staff. There is no charge for our services to NIH customers. You can have outside collaborators on your review; only one NIH person is required. Contact us to request more information or set up a consultation.
How long does it take to complete a review?
Timelines for evidence synthesis reviews vary by team, type of review, and topic. Generally, evidence synthesis reviews take 6 to 12 months (Smith et al., 2011; Borah et al., 2017; MGH LibGuide). Rapid reviews should be completed in a matter of weeks, up to 6 months.
Learn more about the nine steps in evidence synthesis reviews.
Where can I take evidence synthesis classes?
We offer a series of classes on evidence synthesis and related topics several times a year. Please check the NIH Library’s class calendar and join our email distribution list for notification of class schedules. You can also watch our on-demand videos on evidence synthesis for more information.
Where can I learn more about evidence synthesis?
Learn more about how to select and conduct an evidence synthesis at our Evidence Synthesis Service webpage. Key manuals and guidelines are available for different types of evidence syntheses.