Tip #48: Searching the Topic Fields in Web of Science Core Collection

Many thanks to Zahra Premji, Health Research Librarian from the University of Victoria Libraries (@ZapTheLibrarian), for this week's post!

We frequently use the Web of Science Core Collection (WoSCC) Topic field for systematic searching in evidence synthesis, because it is a multi-field option that includes relevant fields such as title, abstract, and author-keywords.

What is the Topic field searching?

According to the Web of Science interface, the Topic field in WoSCC searches "title, abstract and author keywords" (January 10th, 2024).

 This is a change from the description that was provided In the past (as recently as November 2023), where the Topic field description specifically mentioned title, abstract, author keywords, and keywords plus. So the removal of Keywords Plus from the Topic field description is a recent change. But you will see below that despite the field description (on the database) not mentioning Keywords plus, the TS field still includes Keywords plus! I am unsure why the change happened and if it is simply an error or a sign of changes to come. For those not familiar with Keywords plus, they are terms generated from the titles of cited articles; more information about Keywords Plus can be found here.

This post is about understanding how a Topic search parses the search logic if you search a phrase but choose not to (or forget to) enclose it in quotation marks. If you always use quotation marks when searching phrases in Web of Science, then you can skip reading the rest of this post as the search works the way you think it does.

To demonstrate the logic, I ran three sets of searches; single term, phrase with quotation marks, and phrase without quotation marks. In each case, I compared it against what an expanded search would yield using TI/AB/AK/KP.

1. Single term searches in Topic.
2. Phrase with quotation marks in Topic
3. Phrase without quotation marks in Topic

1. Single terms

This example helps us confirm what is being searched in the multi-field Topic option. And we can see from the test below that TS = (TI OR AB OR AK OR KP), and is not (TI OR AB OR AK) as the description in the database seems to imply.

2. Phrase with quotation marks

This example shows that when quotation marks are applied around a phrase, then the search works the way we expect, which is that TS ("phrase") = TI ("phrase") OR AB ("phrase") OR AK ("phrase") OR KP ("phrase"). 

3. Phrase with no quotation marks

This example demonstrates what happens when you search a phrase but do not enclose it in quotation marks. We know that Web of Science automatically puts an AND between terms in a phrase if they are not enclosed in quotation marks. But how does that parse out in a multi-field option such as TS?

So, if you are going to search a phrase in a multi-field option such as TS (Topic) and you want those terms to be searched as a phrase, then use quotation marks. If you are OK with the words in the phrase to be separate, but still want them found in each distinct field, then you would need to create a search string similar to 2 above. Otherwise, Web of Science will simply parse the logic as in 3 above, which allows the terms to be found in separate fields, rather than the same field.