EndNote

De-duplication tool

If you have imported references on the same subject from more than one online resource, you may find that you have some duplicate references in your library. It is important to remove duplicates if you intend to use EndNote with Word to cite references, to avoid errors in your bibliography.

EndNote will search the currently selected references for duplicates. To search the whole EndNote Library, click on the All References folder.

• Go to the Library menu and select Find Duplicates.
• Compare duplicate references to decide which to keep. The display automatically highlights any differences it has detected between the references, if any. You can copy and paste information between references if necessary.
• If you select Keep this record the other record will be sent to Trash.
• If you want to keep both records, or decide later, click on Skip to go to the next duplicate.
• If you decide to Skip or Cancel, references are held in a temporary Duplicate References group.
  • This Duplicate References group is discarded when you close your library.
  • Duplicate references are highlighted. To delete all the automatically detected duplicates, click on one of the highlighted references, hold down the left mouse button and drag across to the Trash folder.  Alternatively you can right-click on any highlighted reference and select Move references to trash. All of the highlighted references will be transferred to the Trash folder.

Manual de-duplication

To catch any outstanding duplicates it can be helpful to manually look through your library.

• Make sure to organise your centre pane where your references are displayed so that you can see all the useful fields clearly to help you judge whether a reference is a true duplicate.
• It can also be useful to choose the Annotated output style in the Preview panel at the bottom of the Summary panel, so that the preview includes the abstract.
• Sort your references by the Title field by clicking on the column header. You can then look through to check for duplicate titles - although be aware that sometimes different publications can have the same title.  A second check where references are organised by DOI is useful, although not all records will have a DOI (and in some cases the DOI might be the same for different references, e.g. conference abstracts). Checking by page number is also helpful.

You can change the sensitivity of EndNote’s duplicate detection:

• Go to the Edit menu and select Preferences.
• Click on Duplicates from the left hand menu.
• Select the fields that are compared when a duplicate search is carried out - this will allow you to compare more fields such as author, year or journal title.
• The Criteria box below gives you an option to scan only for an exact match only or to ignore spacing and punctuation.
• Click on OK.

This short video (1 min 3 secs) from Clarivate explains how to find duplicates in your EndNote library. There is no audio. The video is in EndNote 20, but the process is the same in EndNote 21.