Qualitative research explores people's beliefs, experiences, attitudes, behaviour and interactions. It asks questions about how and why. For example, why people want to stop smoking, rather than asking how many people have tried to stop. It generates non-numerical data, such as a person's description of their pain rather than a measure of pain. Qualitative research techniques such as focus groups and in depth interviews may be used to find out more about the views and experiences of the target population or practitioners.

See Introduction to qualitative research by Healthknowledge.org.uk

Qualitative data: Observations that are categorical rather than numerical, and often involve knowledge, attitudes, perceptions, and intentions. (CDC evaluation glossary)

See also, quantitative research