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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 PubMed 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,  Section 4.5 of the Handbook gives guidelines on documenting and reporting the search process.[1] These sections continue on to discuss the MECIR and PRISMA reporting requirements. The Handbook is supplemented by Methodological Expectations of Cochrane Intervention Reviews (MECIR) Standards for the conduct and reporting of new Cochrane Intervention Reviews. [2]

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) Statement
http://www.prisma-statement.org/

The Statement consists of an item checklist and a flow diagram.  It has been published in several journals; Liberati et al [3] explain the original PRISMA statement in detail.  Relevant to the search process and reporting of the searches are:

  • Information Sources : how to describe the sources searched
  • Search :  includes an example and explanation of a search strategy
  • PRISMA Flow Diagram :  Illustrates the flow of information through the different phases of a systematic review 

The PRISMA checklist includes:

Item 7:  Describe all information sources (e.g., databases with dates of coverage, contact with study authors to identify additional studies) in the search and date last searched.

Item 8: Present full electronic search strategy for at least one database, including any limits used, such that it could be repeated.[4]

The PRISMA Flow Diagram depicts the flow of information through the different phases of a systematic review. It maps out the number of records identified, the numbers included and excluded, and the reasons for exclusions.[5] See Appendix 1 for an example of a PRISMA Flow Diagram. A number of PRISMA Extensions are available, such as those concerned with reporting scoping reviews, diagnostic tests or protocols. See the PRISMA website for links to the original statements and ongoing updates.  

Other sources of guidance, standards and methods.

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

CDR  https://www.york.ac.uk/crd/   has complied a comprehensive set of resources, guides, articles and reports on all aspects of evidence gathering and synthesis. It has published Systematic Reviews: CRD’s guidance for undertaking reviews in health care [6] which is a complete open access guide to all aspects of undertaking a systematic review from inception to completion.  

In conjunction with the UK’s National Institute for Health Research (NIHR), CRD produces PROSPERO which is an international database of prospectively registered systematic reviews in health and social care, welfare, public health, education, crime, justice, and international development. Key features from the review protocol are recorded and maintained as a permanent record. PROSPERO aims to provide a comprehensive listing of systematic reviews registered at inception to help avoid duplication and reduce opportunity for reporting bias by enabling comparison of the completed review with what was planned in the protocol. PROSPERO registered review protocols are themselves excellent examples of the structuring and presentation of a systematic review protocol. The PROSPERO database is available at:  https://www.crd.york.ac.uk/prospero/

Funders increasingly require that systematic review protocols be registered in an appropriate registry. Further information on the available options is available on request.

The Johanna Briggs Institute

The Johanna Briggs Institute  JBI  based at the University of Adelaide is a global service commissioning, undertaking and disseminating evidence based reviews and it has created a set of resources to support evidence based synthesis. https://joannabriggs.org/ 

JBI develops and delivers unique evidence-based information, software, education and training designed to improve healthcare practice and health outcomes. The JBI Manual for Evidence Synthesis is designed to provide authors with a comprehensive guide to conducting JBI systematic reviews. It describes in detail the process of planning, undertaking and writing up a systematic review using JBI methods. The JBI Manual can be used in conjunction with the support and tutorials offered at the JBI SUMARI Knowledge Base. JBI Manual for Evidence Synthesis is available at https://wiki.jbi.global/display/MANUAL

EQUATOR  Enhancing the QUAlity and Transparency Of health Research

EQUATOR [7] 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] Higgins JPT, Thomas J, Chandler J, Cumpston M, Li T, Page MJ, Welch VA (editors). Cochrane Handbook for Systematic Reviews of Interventions version 6.1 (updated September 2020). Cochrane, 2020. https://training.cochrane.org/handbook/current/chapter-04#section-4-5

[2] Methodological Expectations of Cochrane Intervention Reviews (MECIR) Standards for the conduct and reporting of new Cochrane Intervention Reviews, reporting of protocols and the planning, conduct and reporting of updates by Julian PT Higgins, Toby Lasserson, Jackie Chandler, David Tovey, James Thomas, Ella Flemyng and Rachel Churchill Version March 2020. Available at https://community.cochrane.org/sites/default/files/uploads/Version%20March%202020%20Final%20Online%20version.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] PRISMA Checklist. Available from: http://www.prisma-statement.org/PRISMAStatement/Checklist

[5] PRISMA Flow Diagram.  Available from: http://www.prisma-statement.org/PRISMAStatement/FlowDiagram

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

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

Bibliographic and analytic tools for systematic reviews

The principle tool for the management of large volumes of bibliographic references is EndNote. EndNote enables the import of references from all databases, de-duplication, the sharing of references by topic. EndNote facilitates the annotation of references for inclusion or exclusion in the scanning phase of reviews. RCSI has a general licence for desktop copies of EndNote for all users.

There are a number of analytic and management applications commonly used for systematic review projects which facilitate functions like scanning and appraisal, data analysis and normalization, and compilation. 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.  (http://systematicreviewtools.com/index.php)

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; learn more at the Covidence support centre. (https://support.covidence.org/help)

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: more from Cochrane https://community.cochrane.org/help/tools-and-software/revman-5

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. https://eppi.ioe.ac.uk/cms/Default.aspx?tabid=2967

DistillerSR
DistillerSR is a powerful enterprise level application for complete project management. Various pricing plans are available for students, researchers and collaborative groups. https://www.evidencepartners.com/products/distillersr-systematic-review-software/

Rayyan
Rayyan is a free web application to facilitate authors in sharing, reviewing and rating studies. https://rayyan.qcri.org