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HSL Librarians & Assistants Toolkit: Systematic Review Workshop Series Test Page

Supporting Health Sciences Librarians and Library Assistants in improving workflow and the practice of librarianship and library sciences.

Deduplication for Systematic, Scoping, and Rapid Reviews

  • Deduplication is the process of removing duplicate records from review searches.
  • Duplicate records happens with searches are done in multiple databases and all the results from the search are downloaded into Endnote or reference management systems like Mendeley or Zotero.
  • Deduplication is done prior to screening.

Systematic Review Workshop Series Videos

(video and slide deck coming on March 31, following the presentation from the Workshop series on March 29. Register here, if you are interested in the attending this session)


Deduplication Steps

  1. Download search results from all databases in RIS or XML format upon the completion of a database search. Select the file format recommended by the reference management tool or screening tool being used (RIS format is the most likely format).
  2. Decide on de-duplication method: 
    1. Use screening tool's built in algorithm (most screening tools will identify duplicates and ask you to screen them). Recommended for lower numbers of results 1-1000.
    2. The McGill Method (an adapted adapted version of an early version of the Bramer Method): Requires the use of Endnote. Recommended for results over 1000 records. 
    3. The Bramer Method. This is a complex method that requires the use of Endnote, it catches most, if not all duplicates and can save time if you have a high number of articles. See these videos for a demonstration of how the method is applied. Recommended for results over 1000 records
  3. De-duplicate results
  4. Import de-duplicated results into screening tool (i.e. Covidence, Rayyan, DeStillerDR,...)