Interrogative methods allow you to collect data by interacting with the participants, not just by observing their behaviors.
Below in an example of Interrogative methods in action:
Focus Groups
This method allows you to discuss problems and solutions with users as a way to define user requirements of a system. This is typically conducted as a moderated session with about 6-8 participants with similar experience regarding the area or system of interest. The overall goal is to gain insight into user needs, expectations, and experiences as a basis for system specifications to include.
Example
Research Question: What are the needs, expectations, and problems users experience when managing mobile email apps?
A 30 minute focus group session was conducted with five individuals structured similarly to Garmer, Ylvén, and Karlsson (2004), beginning with some introductory questions. Some of these questions and topics included:
What are your general feelings about that (managing emails with mobile email apps)?
What email mobile apps do you use?
How often do you use your mobile app to manage your emails?
Do you manage multiple accounts on that app? How many?
What do you like best about using the app to manage emails?
What problems have you encountered when managing emails on the app?
What solutions have you tried to solve those problems?
Follow-up questions were asked appropriately to dig deeper into topics that participants all related to and identified as an important positive or negative feature of the mobile email app experience.
Things to remember:
Follow where the discussion leads, but keep it on topic. You may uncover user needs, expectations, and experiences that you did not originally plan for.
Ensure that all participants have an opportunity to voice their experiences. Some participants are more talkative than others, but all of them have valuable feedback to offer.
Pros:
Can collect personal accounts and examples of real experiences.
Can collect large sums of data in short periods of time.
Ability to identify common experiences among participants.
Cons:
Discussion is retrospective, and therefore may be less accurate.
Depending on size of focus group, not all individuals may get the chance to voice their experiences.
Can be difficult to stay on topic so that all participants can contribute, rather than continuing with one person specifically.
References:
Garmer, K., Ylvén, J., & MariAnne Karlsson, I. C. (2004). User participation in requirements elicitation comparing focus group interviews and usability tests for eliciting usability requirements for medical equipment: a case study. International Journal of Industrial Ergonomics, 33(2), 85-98. 10.1016/j.ergon.2003.07.005