Finding scientific information

A proximity operator is used to search for words that appear close to each other. The number attached to the proximity operator defines the maximum number of words that can appear between the search terms. All strings are counted as words, including articles (a, an, the) and prepositions (in, for, etc.).

Proximity operators are database-specific and are not available in all databases. Check the Database quick guides for instructions on using proximity operators.

When to use a proximity operator?

• Use a proximity operator instead of the AND operator when you want to ensure that the words appear in the same context—close to each other in the document.
• The proximity operator is also more flexible than phrase searching when the concept can be expressed in different ways (e.g., energy policy, policy on energy, policy for renewable energy).

In Scopus, the proximity operator W/2 retrieves references where the search terms appear with no more than two words between them. The words can be in any order. For example, the search plastic W/2 waste will find variations such as: plastic wastes, plastic solid waste, waste plastics. Scopus 26.5.2025.

Proximity operators are database-specific and are not available in all databases. Therefore, it's always advisable to check the Database quick guides before using a proximity operator.

Many databases support two types of proximity operators. For example, in Scopus, the proximity operator W/n allows the connected words to appear in any order in the search results. The operator PRE/n, on the other hand, requires the words to appear in the specified order.

Scopus as an example:

• W/n (Within n words): This operator finds results where the search terms appear within n words of each other, in any order.
  • Example: climate W/3 change would match "climate change" and "change in climate" and "change in Northern climate".
• PRE/n (Preceding n words): This operator also finds terms within n words of each other, but in the specified order.
  • Example: climate PRE/3 change would match "climate change" but not "change in climate".

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: