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Doing a Systematic Review

A concise guide to the steps involved in systematic, scoping and related reviews

What is a systematic review?

Systematic reviews (SRs) are one of the hardest things you can do academically… but one of the most rewarding. They can find actual answers to real-world problems – even if that answer is “we don’t know the answer yet”.

A systematic review should:

  • Answer a focused question
  • Use a comprehensive, reproducible search strategy
  • Identify ALL relevant studies (published and unpublished), unless certain types are specifically excluded
  • Evaluate all results for inclusion and quality
  • Bring together the findings in an unbiased way and present a balanced summary

To avoid bias, an SR is usually run by at least two researchers, but this may not be possible - if so, it should be noted as a limitation of the review. Professional reviews will often involve large teams looking at complex research questions. Such large studies can take months or even years to complete.

Getting help

Your Subject Librarian can give advice on some of the steps in the process, such as choosing where to search (step 2), developing a search strategy (step 3), running & recording your search (step 4) and managing your search results (step 5). Refer to your supervisor for help with developing your protocol, evaluating the studies and writing up the review.

How does it differ from a systematic literature search?

You may be asked to do a systematic review, when what your supervisor actually wants you to do is a systematic review of the literature. There are some very key differences:

Systematic review Systematic literature review
Brings together the results of studies to answer a specific question Provides a subjective summary of the literature on a topic
Extensive search covering published and grey literature Thorough search of published literature
Involves a detailed protocol often developed using the PICO framework Includes a detailed search strategy
Usually involves three or more people to eliminate bias  Can be produced by a single person, so open to bias
Can take months or years to produce Weeks or months to produce


  • A detailed protocol
  • Systematic search strategy
  • Review of results against eligibility criteria
  • Evaluation of studies
  • Interpretation and presentation of results
  • Extensive reference list
  • Detailed appendices showing search strategies


  • Introduction
  • Methods - search strategy
  • Discussion
  • Conclusion
  • Long reference list

A type of review that uses elements of a systematic review might be called a systematised review. Rapid reviews are also conducted using elements of the methodology, as are scoping reviews.

Summary adapted from: Kysh, L. (n.d.) What's in a name? The difference between a systematic review and a literature review and why it matters.

Other types of review

Other types of review

There are many other types of review including:

  • Scoping review
    An initial assessment of the size and scope of research literature on a topic. Can be the first step in a systematic review.
  • Rapid review
    Uses systematic review methods to search and critically appraise existing research to find out what is already known about a topic.
  • Meta-analysis
    A statistical approach to combining the data derived from from a systematic review.
  • Narrative review
    Uses description rather than statistics to analyse the findings from relevant primary studies.

For a more comprehensive overview of review types see the page below from Duke University:

Systematic reviews summarised

The following videos offer two explanations of systematic reviews and what's involved in doing them.

Find existing systematic reviews

The following is a selection of databases giving access to reviews in different subject areas.

Other guides to doing systematic reviews