PRESS Peer Review of Electronic Search Strategies: 2015 Guideline Explanation and Elaboration


Project Line:
Health Technology Review
Project Number:

It is believed that quality is enhanced when there is peer review of the electronic search strategies developed for systematic review (SR) and health technology assessment (HTA) reports. The PRESS Guideline provides a set of recommendations concerning the information that should be used by librarians and other information specialists when they are asked to evaluate these electronic search strategies. This guideline updates and expands upon the 2008 CADTH report PRESS: Peer Review of Electronic Search Strategies, as well as An Evidence Based Checklist for the Peer Review of Electronic Search Strategies (PRESS EBC), published in the Evidence Based Library and Information Practice journal in 2010.

The full guideline statement and checklist document may be accessed via the following open access article from the Journal of Clinical Epidemiology:
McGowan J, Sampson M, Salzwedel DM, Cogo E, Foerster V, Lefebvre C. PRESS Peer Review of Electronic Search Strategies: 2015 guideline statement. J Clin Epidemiol. 2016 Jul;75:40-6.


The objectives of this document are, as follows:

  • an SR to identify the evidence base regarding elements to guide an evaluation of electronic search strategies
  • a Web-based survey to assess expert opinion regarding elements to guide an evaluation of electronic search strategies
  • a consensus forum meeting to obtain consensus among experts regarding elements to include in proposed recommendations and guidance regarding the evaluation of electronic search strategies
  • developing recommendations and guidance for librarians and other information specialists
  • updating the PRESS Evidence Based Checklist
  • knowledge translation including producing a CADTH report.

In addition, the authors of this report intend to publish in the medical literature.


The SR, Web-based survey and consensus meeting explored the following questions:

  • Are there any existing checklists that evaluate or validate the quality of literature searches in any discipline?
  • What elements relate to quality or errors in search strategies?
  • The SR search focused on primary research and secondary reports on electronic search strategies within a health science context. For this update, the following databases were searched: Ovid MEDLINE and MEDLINE In-Process (January 2005 to April, week 1, 2015) on April 4, 2015 and the Cochrane Methodology Register and Cochrane methodology reviews (the Cochrane Library online) on May 29, 2015. Grey literature was identified by contacting information specialists and other experts. There were no language restrictions. Bibliographic records retrieved by the literature searches were assessed for their relevance to the peer review process. A calibration exercise was used for the assessment of eligibility. Potentially relevant articles were retrieved, and two reviewers assessed each of the full reports for eligibility. Abstracted information was recorded in DistillerSR SR software using a standardized form adapted from the form used in the original review. Data were summarized descriptively and synthesized narratively.

A Web-based survey of expert SR searchers was undertaken using a PRESS survey tool developed by the project team and reviewed by CADTH staff. The survey was launched after the completion of the SR, enabling those search strategy elements identified in the review to be included in the survey of experts. When these results were available, a consensus forum discussed the results of the SR and survey. Recruitment for the survey included sending messages to mailing lists, personal email invitations to authors of relevant publications, and messages to PRESS consensus forum teleconference participants. Data were analyzed quantitatively using Excel, and the narrative responses will be qualitatively analyzed.


A recent SR, Web-based survey of experts and a consensus forum upheld the six of the seven elements of the PRESS tool for peer review, while adding adjustments to the existing guidance for searchers and peer reviewers