Duplicated citations are a common problem when conducting extensive literature searches, especially when compiling a systematic review or a literature review.
Some individual databases may give you the option to exclude duplicate citations when you place a search. To check whether this is possible, it is usually best to explore the Advanced Search options for that database and see whether there is any tick box or setting you can use. Alternatively, check the database's in-built help pages to see if they offer any advice.
Unfortunately not all databases or catalogues will have their own function for removing duplicates, so most students will instead need to use reference management software in order to deal with any duplicates. At the University of Wolverhampton our preferred reference management tool is Refworks - you can register for an account using your University email address. This FAQ explains how.
Once you have a Refworks account, you can export ALL of your search results from each database into the Refworks system and then use the Refworks 'Find duplicates' tool to discover and delete the unwanted citations. At the time of writing, this option is under the Tools menu:
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Further advice on this can be found as part of Refworks 'Managing References' support page (scroll down towards the bottom of the link)
