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Systematic Reviews

Saving Searches, Setting Up Alerts and Updating the Searches

Saving Searches, Setting up Alerts and Updating the Searches

Each database enables searchers to create their own personal accounts which is very useful for saving and storing both searches and search results.  Into your account, you can save:

  • Search strategies to rerun at a later stage
  • Set up alerts, whereby you will get an email alerting you to new items added to the database which match up with your search
  • Individual items organised into collections or folders

In My NCBI for instance, PubMed saves the search strategy as one long string :

           Search (deep vein thrombosis) AND (aspirin) AND (travel OR aircraft OR airplane)

If you wish to capture all the elements of the search history (search number, description of words used, no of items found), use the Download History option in Advanced Search and the history will be saved into a spreadsheet.

If you set up alerts on each database, then you don’t need to run the searches again.  However, if you haven’t done so, then it is important to re-run the searches exactly as you did originally in order to capture any additional studies published since your last search.

Standards

There are several standards for the reporting of reviews, which include the reporting of the search strategies.

Cochrane Collaboration

Cochrane Handbook for Systematic Reviews of Interventions[1]

Chapter 11.2 Results of the search and selection of studies

Concentrates on a study flow diagram, using PRISMA as an example

               

Methodological Expectations of Cochrane Intervention Reviews (MECIR) Project[2]

The MECIR project has drawn up standards for the conduct and the reporting of Cochrane Intervention Reviews.  Very useful to follow even if you are not doing a Cochrane review – use as a checklist. Each standard is either mandatory or highly desirable and the exclusion should be justified. A rationale and elaboration of each standard is included as well as a reference to the relevant section of the Cochrane Handbook. 

Methodological standards for the reporting of Cochrane Intervention Reviews, version 1.1,  17 Dec 2012, Items R34-R39:

Item R34      Search sources

Item R35      Latest searches

Item R36      Search timeframe

Item R37      Searches for different types of evidence

Item R38      Search strategies for bibliographic databases

Item R39      Search strategies for other sources  

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Statement 

The Statement consists of a 27-item checklist and a flow diagram.  It has been published in several journals, together with an Explanation and Elaboration document.  See the PRISMA website for links to the journal articles.

Liberati et al[3] explain the PRISMA statement in detail.  Relevant to the search process and reporting of the searches are:

Item 7                   Information Sources

                             Includes an example of how to describe the sources searched

Item 8                   Search

                             Includes an example and explanation of a search strategy

Figure 1                PRISMA Flow Diagram

Illustrates the flow of information through the different phases of a systematic review  (see Appendix 1.)

The Cochrane Handbook (Chapter 11.2) has published an example of using the PRISMA flow diagram.[4]  

Centre for Reviews and Dissemination (CRD), University of York.

In Systematic Reviews: CRD’s guidance for undertaking reviews in health care[5],  Appendix 3 deals with documenting the search process and has a useful sample OVID search strategy which could be added as an appendix.  It also explains how to describe the search strategy within the text of your review.  Available at: https://www.york.ac.uk/media/crd/Systematic_Reviews.pdf

EQUATOR  Enhancing the QUAlity and Transparency Of health Research

EQUATOR[6] collates the different reporting standards applied to different study types:

  • Randomised trials : CONSORT                    
  • Observational studies :  STROBE               
  • Systematic reviews :  PRISMA                   
  • Diagnostic/prognostic studies : STARD   
  • Clinical practice guidelines : AGREE          
  • Qualitative research : SRQR        
  • Economic evaluations : CHEERS

[1] Schünemann HJ, Oxman AD, Higgins JPT, Vist GE, Glasziou P, Guyatt GH. Chapter 11: Presenting the results and “Summary of findings tables”. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions. Version 5.1.0 [updated March 2011]. The Cochrane Collaboration, 2011. Available from http://www.cochrane-handbook.org   

[2]Higgins JPT, Lasserson T, Chandler J, Tovey D, Churchill R. Methodological Expectations of Cochrane Intervention Reviews. Cochrane: London, Version 1.02.2016. Updated Jan 2018.  Available from:  https://community.cochrane.org/sites/default/files/uploads/MECIR%20PRINTED%20BOOKLET%20FINAL%20v1.02.pdf

[3] Liberati, A et al. The PRISMA Statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Medicine 2009 6(7): e1000100

[4] Schünemann HJ, Oxman AD, Higgins JPT, Vist GE, Glasziou P, Guyatt GH. Chapter 11: Presenting the results and “Summary of findings tables”. In: Higgins JPT, Green S (editors). Cochrane Handbook for Systematic Reviews of Interventions. Version 5.1.0 [updated March 2011]. The Cochrane Collaboration, 2011. Available from  http://www.cochrane-handbook.org

[5] Centre for Reviews and Dissemination, University of York. Systematic Reviews: CRD’s guidance for undertaking reviews in health care. University of York, 2008. Available from http://www.york.ac.uk/inst/crd/index_guidance.htm

[6] EQUATOR Reporting guidelines for main study types.  Available from   https://www.equator-network.org/

Software and Tools

There are a number of applications and tools which were developed by various producers to aid in the management and analysis of information for systematic review projects.  One site that attempts to collate information about these tools is called SR Toolbox, compiled by Dr Chris Marshall of Newcastle University in the UK.  

The Systematic Review Toolbox

The Systematic Review Toolbox is a community-driven, searchable, web-based catalogue of tools that support the systematic review process across multiple domains. The resource aims to help reviewers find appropriate tools based on how they provide support for the systematic review process.

SR Toolbox currently reviews applications and tools in the following categories. 

  • Protocol Development
  • Automated Search
  • Study Selection
  • Quality Assessment
  • Data Extraction
  • Automated Analysis
  • Text Analysis
  • Meta-Analysis
  • Report Write-Up
  • Collaboration
  • Document Management

Some of these utilities are free to download, some are for one off purchase, some are subscription based. Tools may require sophisticated statistical and data analysis support and the advice of experienced researchers should always be sought. RCSI as an institution does not provide direct support or financing for systematic review applications or utilities.

Some of the more widely used systematic review applications include the following:

Covidence
Covidence is an online systematic review program developed by, and for, systematic reviewers. It can import citations from reference managers like EndNote, facilitate the screening of abstracts and full-text, populate risk of bias tables, assist with data extraction, and export to all common formats. Covidence is a core component of Cochrane's review production toolkit.

Review Manager
RevMan 5 was developed for preparing and maintaining Cochrane Reviews and it facilitates preparation of protocols and full reviews, including text composition, characteristics of studies, comparison tables, and study data. It can perform meta-analysis of the data entered, and present the results graphically. RevMan also presents templates to write reviews of diagnostic test accuracy studies, reviews of studies of methodology and overviews of reviews. Offline, desktop version free to download from Cochrane.

EPPI-Reviewer
EPPI-Reviewer 4 is a web-based software program for managing and analysing data in literature reviews. It has been developed for all types of systematic review, including meta-analysis, framework synthesis and thematic synthesis. It manages references, stores PDF files and facilitates qualitative and quantitative analyses such as meta-analysis and thematic synthesis. The Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI-Centre) is part of the Social Science Research Unit at the Institute of Education, University of London.

DistillerSR
DistillerSR is a powerful enterprise level application for complete project management. Various pricing plans are available for students, researchers and collaborative groups. 

Rayyan
Rayyan is a free web application to facilitate authors in sharing, reviewing and rating studies. 

 

More information

Software tools for literature screening in systematic reviews in biomedical research. Van der Mierden S et al.  ALTEX. 2019;36(3):508-517. doi: 10.14573/altex.1902131. Epub 2019 May 16.

Software tools to support title and abstract screening for systematic reviews in healthcare: an evaluation. Harrison H, Griffin SJ, Kuhn I, Usher-Smith JA.. BMC Med Res Methodol. 2020 Jan 13;20(1):7. doi: 10.1186/s12874-020-0897-3.

Rayyan-a web and mobile app for systematic reviews. Ouzzani M et al. Syst Rev. 2016 Dec 5;5(1):210.