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Screening

How to Screen | Pilot Test | Get Full Text | Manuals & Guidance

How To Screen

Screening (or study selection) involves choosing articles from search results based on pre-set inclusion criteria, and is conducted at two stages:

  • Stage one: read titles and abstracts and exclude irrelevant articles per your eligibility criteria  
  • Stage two: read the full text of the article to ensure it meets all your inclusion criteria.  

Following pre-set criteria reduces the risk of introducing bias.

For both stages, each article is independently screened by two reviewers. You can have more than two reviewers conduct screening (e.g., four people on your team serve as screeners).  

It is critical that a process to resolve disagreements or conflicts between the two reviewers is determined and documented in the protocol. You can resolve disagreements by consensus discussion amongst the two reviewers or entire review team, or by a separate third reviewer.

Pilot Test

Pilot testing your eligibility criteria, screening process, and software allows the team to  

  • Refine and clarify the eligibility criteria  
  • Ensure the reviewers understand the criteria and apply them consistently
  • Try out the software used for screening    

The entire team should participate in the pilot. Afterwards, the team should discuss and resolve disagreements, answer questions, and modify the eligibility criteria. Document changes you make in the review protocol. JBI recommends starting to officially screen only once 75% or more agreement is achieved between the reviewers.

How many records to use?  

Depending on the review topic, pilot with at least 25 to 50 or more articles (JBI) and include examples of articles that are definitely eligible, definitely not eligible, and ambiguous (Cochrane).

Learn more about pilot testing:

  • Peters M, Marnie C, Tricco A, Pollock D, Munn Z, Alexander L, McInerney P, Godfrey C, Khalil H. Updated methodological guidance for the conduct of scoping reviews.(2020).  JBI Evidence Synthesis 18(10):p 2119-2126.
  • Peters MDJ, Godfrey C, McInerney P, Munn Z, Tricco AC, Khalil, H. Chapter 10: Scoping Reviews - 10.2.6 Source of evidence selection. (2020). In: Aromataris E, Lockwood C, Porritt K, Pilla B, Jordan Z (editors). JBI Manual for Evidence Synthesis. JBI; 2024.
  • Lefebvre C, Glanville J, Briscoe S, Featherstone R, Littlewood A, Metzendorf M-I, Noel-Storr A, Paynter R, Rader T, Thomas J, Wieland LS. Chapter 4: Searching for and selecting studies - 4.6.4 Implementation of the selection process. In: Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.4 (updated October 2023). Cochrane, 2023.

Get Full Text

Stage two of screening requires the full text of articles usually as a PDF. This is a multi-step process to identify, obtain, and upload the PDFs into the software used.

You do not need to wait until all the full texts are available to begin full text screening. You will need the full text for data extraction too, so take the time to obtain the needed full texts now.

We recommend using EndNote or another citation management tool that has “find full text” capabilities to obtain articles based on the NIH Library’s licenses. This step saves time and downloads most of the full texts needed. NIH staff, please see this page for more information on setting up EndNote.

If you used Covidence for screening, follow the steps for bulk importing the PDFs for full text screening. Also, Covidence, which is used for screening, will automatically find and attach the full text for open access articles.

Request articles not retrieved through EndNote’s find full text feature through the NIH Library’s document delivery service. This is a free service for NIH and select HHS staff.  

Speak to the NIH Librarian working with your evidence synthesis review team for more information.

For NIH and HHS staff contact your IT staff to have EndNote downloaded to your US government computer.

Learn more about finding full text:

Manuals & Guidance

For more details and guidance on screening, please consult the following resources. You can also ask a NIH Librarian for additional help.

Next > Using Covidence

Eligibility Criteria | Screening | Using Covidence | Risk of Bias | Data Collection | Data Synthesis