My former colleague Fiona has started a monthly journal club on her blog, and this month’s article about Boolean searching piqued my interest. Fiona posted a couple of questions to get the discussion going, and I thought I’d contribute my opinions to the discussion. In case you haven’t guessed from the title of the post, I’m a fan of Boolean searching. I’ll be wearing and swapping between two hats in these answers – my hospital librarian hat, and my tutor-in-a-unit-within-a-Masters-level-library-and-information-studies-course hat. Please note that these are my thoughts on the topic, and do not represent the views of my day-to-day employer or the university which employed me. Now, onto my answers.
Do you teach Boolean searching? Why/why not?
Firstly I should note that as a hospital librarian I don’t do any teaching of undergraduate students (the group who were the subject of the article). However, I do provide search training to hospital staff (usually in a one-on-one setting). In these sessions I do teach Boolean searching in a sense, but I usually don’t refer to it as “Boolean” and I don’t go into any great detail (and I don’t use any Venn diagrams). This is because we don’t have access to a discovery tool, so all our searching is done in medical databases (usually MEDLINE and EMBASE on the Ovid platform). These work best with structured searches.
The situation is different when I’m teaching in the Masters-level information retrieval unit. Boolean operators are covered in lectures and tutorials, and students are assessed on their use of Boolean in a couple of their assignments. I think it makes sense to teach future information professionals how to effectively use Boolean operators, because there are still situations (such as using subject-specific databases) where Boolean is the most effective way to construct a search.
If you teach Boolean only to some students, or in some circumstances, what is behind the decision to teach or not to teach?
As I mentioned above, the databases that I’m showing hospital staff how to use work best with Boolean searches, so that’s why I show them how to use the Boolean operators in their search. However I rarely use the term “Boolean” when I’m describing how to build a search; I’ll talk about combining the search terms using AND or OR. The database platform that I demonstrate (Ovid) has handy AND and OR buttons located on the search page, so it’s easy to say “now you can combine these terms using AND to retrieve the documents that contain all of these terms”. Some of the staff might say something like “Oh, you mean a Boolean search?”, but I don’t mention the B-word.
Do you think that there are any information retrieval advantages to using Boolean search strategies over natural language? When?
I believe that Boolean search strategies have the advantage of being able to construct a highly-targeted and specific search, especially when using subject headings. They also make it easy to combine the search terms in different ways or add in different terms if you need to tweak your search without having to type out a new search strategy each time.
Do you think that there are any pedagogical advantages to teaching Boolean search strategies as opposed to natural language? Why/why not?
One advantage that I see in using Boolean search strategies is that they encourage the searcher to think about their topic in more depth, rather than just typing a phrase into a search engine or database and hoping for the best. The search works better once the key concepts have been identified, along with any synonyms that can be included alternative search terms. This is the approach that I use as a tutor, and I think it’s effective in helping the students build an effective search strategy.
There’s an additional advantage that I think comes with using subject headings with Boolean operators. Although subject headings and the way that they’re structured can be daunting for someone not familiar with a subject, they can help them get a better understanding of the vocabulary of the subject.
What other search strategies do you teach either alongside or instead or Boolean? Why those?
It’s not a search technique per se, but the PICO framework is another tool that I show hospital staff. PICO is commonly used in the health sector, especially in evidence-based medicine, to help clinicians and researchers come up with a focussed clinical question. Because it consists of distinct components, it lends itself nicely to a structured search using Boolean operators i.e. P AND I AND C AND O.
Although some of the points that I’ve made aren’t directly relevant to the article, I hope this post has given you a bit of an insight into why I think Boolean searching is still worth using. Long live Boolean!