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When should you use E-utilities?


Please note: following the release of the new version of PubMed, the results returned by E-utilities queries of PubMed may differ slightly from those returned in the web version of PubMed. A new PubMed API is currently under development: more information will be announced when available.

As new Insider's Guide classes are no longer being offered, this site is not currently being updated. Please refer to NCBI's E-utilities documentation for more up-to-date information.


If you have a question that cannot be answered easily when you search PubMed, you might want to consider using E-utilities to get your answer.

Maybe you want to:

  • see every citation in PubMed for which there is no data or any data in a certain field.
  • find the MeSH term that occurs most frequently with another MeSH term.
  • run a search in PubMed and get the output in a CSV file that includes more (or different) data elements than the standard CSV file. (PubMed’s “Send to” menu allows you to create a CSV file, but this file only includes selected data elements.)

These are specialized queries that might serve a very specific research need. With E-utilities you can get the data that you need, and only the data that you need, in the format that you need.

If you are reading this introduction and are already thinking of queries that are outside the scope of a PubMed search, then E-utilities might be a good tool for you. It takes a little bit of time to get up and running with E-utilities – you might need specific software and skills to get started. But the Insider’s Guide series of classes is designed to help you with that!

E-utilities is a great solution when you:

  • can’t find a good way to ask your question using the PubMed search box.
  • can search PubMed, but you’d like more, or less, or different data returned from the records.
  • want more control over the format of your PubMed data.