Tip #27: PubMed Subheadings Continued...

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ETA: Many thanks to Whitney Townsend for being a second set of eyes to check my testing strategies!

Building on our earlier post, Tip #25: Using Subheadings in PubMed, here are some more fun things to know about PubMed's subheadings... 

Did you know that PubMed's subheadings have their own hierarchy? You can see the full list of Subheadings categories in the MeSH database.

And just like you find with other MeSH terms, PubMed also automatically explodes subheadings.  For example, when you search "Blood Glucose/analysis"[Mesh], you are getting all of the relevant lower-level subheadings under "analysis" [Subheading]. 

This MeSH and subheading combo includes:

  • "Blood Glucose/analysis"[Mesh]
    • "Blood Glucose/blood"[Mesh]
    • "Blood Glucose/isolation and purification"[Mesh]
    • "Blood  Glucose/cerebrospinal fluid"[Mesh]

In the screenshot below, you can see that ORing the other subheadings in doesn't increase or change our results because they are already included in the broader "Blood Glucose/analysis"[Mesh] search.

If you are floating subheadings in your search, you may run into a search topic where you need to exclude lower level subheadings terms to improve precision. Just as you can turn off explode for MeSH terms, you can also use the same function for subheadings.

 
 
"analysis" [Subheading:NoExp] vs. "analysis" [Subheading]
 
Here's an (entirely made-up, probably not actually relevant for the topic) example just to highlight the difference:


 
Try it (click on the link to run the search)!
#2 ("Diabetes Mellitus, Type 2/diagnosis"[Mesh]) AND ("Blood Glucose"[Mesh] AND "analysis" [Subheading:NoExp]) 

#1 ("Diabetes Mellitus, Type 2/diagnosis"[Mesh]) AND ("Blood Glucose"[Mesh] AND "analysis" [Subheading]) 

Comments

  1. Concepción Campos-AsensioOctober 18, 2022 at 7:52 AM

    Does OVID MEDLINE also do the exploded search for subheadings? Thanks

    ReplyDelete
    Replies
    1. Kate SaylorOctober 20, 2022 at 1:33 PM

      Good question! I'll have to investigate and will likely make a future tip post out of it. A quick test makes me think that it behaves differently:
      blood glucose/an (60639)
      blood glucose/an or blood glucose/bl or blood glucose/cf or blood glucose/ip (60714)

      Delete

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