Finding scientific information: Proximity operators

Proximity operators

Proximity operator is used when the search terms need to be within a certain distance from each other. It defines how many words there can be between two words. Proximity operators are database specific and all databases don't use them. Check the functioning of the proximity operators in the Database quick guide.

When should you use a proximity operator?

  • Proximity operator works better than AND-operator when you are searching for a term in a certain context. You can make sure the terms appear close to each other in a document.
  • Proximity operator works better than a phrase search, when the topic can be expressed with several similar phrases (e.g. plastic waste, waste plastics). 

 

For example, W/2 in the Scopus databases looks for references with search terms max. two words apart, in any order. Scopus 27.7.2018.

Which number should I use with the proximity operator?

The number used with a proximity operator defines how wany words in maximum there can be between the search terms. You can use the following table as a rule of thumb:

Term distance Good for finding... Example
0

Adjacent words.

Useful for finding synonymes for a phrase. Sometimes works also in the databases where automatic stemming or lemmatisation doesn't work inside the quotation marks.

(drinking OR potable) W/0 water

1-5 The words within the same phrase. energy W/3 policy
5-15 The words within the same sentence. Useful especially for full text search. erosion W/10 vegetation
20-50 The words within the same paragraph. Useful for full text search. healthcare W/30 Finland