Which research method combines both quantitative and qualitative questions to understand user opinions?

Surveys are an effective research method because they are designed to gather both quantitative and qualitative data from users. With surveys, researchers can include a variety of question types, such as multiple-choice questions, which provide numerical data (quantitative), as well as open-ended questions that allow users to express their thoughts and feelings in their own words (qualitative). This combination offers a comprehensive view of user opinions, as it not only quantifies responses but also captures deeper insights that numbers alone cannot provide. Utilizing surveys in UX research allows designers to identify patterns and trends while also understanding the reasoning behind users' opinions, thus leading to more informed design decisions.

In contrast, usability studies primarily focus on observing users as they interact with a product to identify areas of improvement, interviews are centered on in-depth conversations with users that yield qualitative insights but often lack structured quantitative data, and pilot studies are typically small-scale trials used to test concepts before wider implementation, which may not focus directly on gathering user opinions in the same manner as surveys do.