Skip to Main Content  

Systematic Review Overview: 3. Conduct a Thorough Literature Search

Introduction to the 8 elements that encompass a systematic review

Step 3. Conduct a Thorough Literature Search

A key component to a successful systematic review involves conducting a comprehensive, thorough literature search. The idea behind doing a methodical search is to be as comprehensive as possible when looking for relevant literature. This helps ensure you don’t miss any potentially useful articles.

Depending on your topic, you may need to search a number of different databases, trials registries, websites, and so on. Other methods include citation tracking, contacting study investigators, experts, and manufacturers. You may also engage in something called, “hand-searching”, which requires you to comb through the reference lists of selected journals for articles that may have been missed in your original database search.

How Many Results are Enough?

This question is frequently asked when conducting searches in support of systematic review topics.

As can be seen in the table below, the numbers of resulting search citations is completely topic dependent, and cannot be established prior to the searching.

How Many Results are Enough?
 Systematic Review Article   Search Results     Total Used  
Atenstaedt and Jones 2011 68 0
Dennis, Hawken et al. 2011 365 38
Leufkens, van den Bosch et al. 2011    779 11
Carroll, Papaioannou et al. 2011 1,444 4
Ford, Khan et al. 2011 3,061 44
Evans, Watson et al. 2011 4,142 40
McGinn, Grenier et al. 2011 5,695 117
Neelam, Garg et al. 2011 8,678 7
Irwin, Yoon et al. 2011 9,760 19
Dickens and Picchioni 2012 13,765 11
Clegg and Young 2011 18,767 14
Chowdhury, Dagash et al. 2007 55,391 163
do Prado, Piovesan et al. 2010 68,528 12


Recommending a Role for Librarians in Systematic Reviews

Please see the following link to a brief document that highlights guidance methodologies that recommend the involvement of information specialists or librarians in systematic reviews: