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How to carry out a literature search for a systematic review: a practical guide

  • Lauren Z. Atkinson and Andrea Cipriani

Performing an effective literature search to obtain the best available evidence is the basis of any evidence-based discipline, in particular evidence-based medicine. However, with a vast and growing volume of published research available, searching the literature can be challenging. Even when journals are indexed in electronic databases, it can be difficult to identify all relevant studies without an effective search strategy. It is also important to search unpublished literature to reduce publication bias, which occurs from a tendency for authors and journals to preferentially publish statistically significant studies. This article is intended for clinicians and researchers who are approaching the field of evidence synthesis and would like to perform a literature search. It aims to provide advice on how to develop the search protocol and the strategy to identify the most relevant evidence for a given research or clinical question. It will also focus on how to search not only the published but also the unpublished literature using a number of online resources.


  • Understand the purpose of conducting a literature search and its integral part of the literature review process
  • Become aware of the range of sources that are available, including electronic databases of published data and trial registries to identify unpublished data
  • Understand how to develop a search strategy and apply appropriate search terms to interrogate electronic databases or trial registries



Corresponding author
Correspondence Professor Andrea Cipriani, Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford OX3 7JX, UK. Email:
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BJPsych Advances
  • ISSN: 2056-4678
  • EISSN: 2056-4686
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How to carry out a literature search for a systematic review: a practical guide

  • Lauren Z. Atkinson and Andrea Cipriani
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