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Systematic Reviews & Other Review Types

This guide will help you get started with your next systematic review, scoping review, or other review types.

Systematic Review vs. Literature (Narrative) Review

Traditional literature review / narrative review:


  • Describes and appraises previous work but does not describe specific methods by which the reviewed studies were identified, selected and evaluated


  • Overviews, discussions, critiques of previous work and the current gaps in knowledge
  • Often used as rationale for new research  
  • To scope the types of interventions available to include in a review


  • The writers assumptions and agenda often unknown
  • Biases that occur in selecting and assessing the literature are unknown
  • Cannot be replicated

Systematic review:


  • The scope of the review is identified in advance (eg review question and sub‐questions and/or sub‐group analysis to be undertaken)
  • Comprehensive search to find all relevant studies
  • Use of explicit criteria to include / exclude studies
  • Application of established standards to critically appraise study quality
  • Explicit methods of extracting and synthesizing study findings (qualitative or quantitative)
  • May include a meta-analysis (quantitative synthesis) *optional


  • Identifies, appraises and synthesizes all available research that is relevant to a particular review question
  • Collates all that is known on a given topic and identifies the basis of that knowledge  
  • Comprehensive report using explicit processes so that rationale, assumptions and methods are open to scrutiny by external parties
  • Can be replicated / updated


  • Systematic reviews with narrowly defined review questions provide specific answers to specific questions  
  • Alternative questions that have not been answered usually need to be reconstructed by the reader  

Source: Cochrane. Background to Systematic Reviews


What is a Systematic Review?


Level of Evidence pyramid

A systematic review is defined as “a review of the evidence on a clearly formulated question that uses systematic and explicit methods to identify, select and critically appraise relevant primary research, and to extract and analyze data from the studies that are included in the review.”  The methods used must be reproducible and transparent.

Source: Undertaking Systematic Reviews of Research on Effectiveness. CRD’s Guidance for those Carrying Out or Commissioning Reviews. CRD Report Number 4 (2nd Edition). NHS Centre for Reviews and Dissemination, University of York. March 2001.  

Image: EBM Pyramid and EBM Page Generator, copyright 2006 Trustees of Dartmouth College and Yale University. All Rights Reserved. Produced by Jan Glover, David Izzo, Karen Odato and Lei Wang.

When is a Systematic Review the most appropriate study design?

When answering questions of effectiveness comparing two different treatments or interventions.

Is your review question a complex intervention? Learn more here

Choosing a Review Type: This guide explains other comprehensive literature reviews of similar methodology to the systematic review.

Here is a helpful article about review types.  (Meeting the Review Family: Exploring review types and associated information retrieval requirements, 2019,Sutton et al.)

You may also find the Review Ready Reckoner helpful! 

7 Stages of Conducting a Systematic Review

1.  Gathering your team (Minimum of two reviewers with a third to serve as a tiebreaker)

2.  Questioning (Define a narrow question, may use PICO)  Is your review question a complex intervention? Learn more about Reviews of Complex Interventions

3.  Planning (Create a priori protocol (See the Prisma-P extension this link will open a PDF document), plan and test the search strategy, register the protocol (PROSPERO-for medical/health sciences, OSF for other disciplines) 

4.  Searching/Screening (Exhaustive, transparent & repeatable searching for evidence/selecting studies) Includes database, grey literature/clinical trial registry and handsearching of the literature. Screening is done in two phases.  The first phase is screening titles/abstracts, the second phase is screening full texts.  Screening is done independently by two reviewers, with a third as a tiebreaker.

See our Systematic Review Search Service for help conducting the search!

5.   Managing & reporting (all methods are transparent and reproducible) 


6.  Synthesizing the evidence (appraising the evidence, interpreting results, performing a qualitative and/or quantitative/meta-analysis-optional)


7.  Drawing Conclusions, Writing & Publishing

Where to register your Systematic Review Protocol?


Moller AM, Myles PS.  What makes a good systematic review and meta-analysis? BJA. 2016. 117(4):428-430.


For additional help

Systematic Review Service:

The health sciences library Chat with a Librarian service is available at Many of our librarians are available to provide systematic review education. Or you may reach the Team Lead, Stephanie Roth: Email Phone (215) 707-9469


Systematic Review Standards