Usability research on tree navigation vs search

Question

I'm working on a mobile app that will display specialized, highly structured contents to professionals. The objective of this app is to be a tool helping them in their work. So the key element for them is to find the relevant information as quickly as possible.

The current prototype allows users to navigate through categories and scrolls alphabetical lists to access a specific content. They can also use specific filters to limit the number of elements to scroll through. To give an idea, there might still be up to 50 elements left even once filter / category are applied.

There is no possibility to filter on multiple criteria at the same time, nor full-text search. The main stakeholders resist implementing these features.

Intuitively, I would think that full-text search would be quicker than navigation, even (or especially) for expert users, to find the relevant specific content they are looking for. But maybe I'm wrong.

I read articles regarding search vs navigation, but they are mostly relevant for web users discovering a website, rather than experts in a professional context, with regular use of an app.

Do you know if usability research has been done in a similar context, which would show the difference in task completion time of browsing vs searching?

PS: the current prototype is static with limited contents, we can't do a usability study of this nature with it.

Answer 1

" So the key element for them is to find the relevant information as quickly as possible."

"There is no possibility to filter on multiple criteria at the same time, nor full-text search. The main stakeholders resist implementing these features."

That just sounds bizarre, as the resistance to implementing a search in the second quote obviously goes against the aim in the first.

I've done a lot of work in tree visualisations and a search function is always asked for, because that's the quickest way to find something you definitely know exists and you want. Browsing a tree can reveal items/categories you didn't know about, but when the users have a definite item in mind a search is the way to go.

There's a few papers that look at searching v browsing outside of websites but all acknowledge they are different operations. Here's one that finds expert users generally preferred direct search if that helps:

Browse and Search Patterns in a Digital Image Database Frost, C.O., Taylor, B., Noakes, A. et al. Information Retrieval (2000) 1: 287. https://doi.org/10.1023/A:1009979200555

You might just have to find a tactful way of telling the stakeholders they're just wrong. Explain search to them as just another filter - it filters out everything that DOESN'T match the search terms. As the rolling stones said: "You don't get what you want, you get what you need"