Qualitative and quantitative usability studies

Qualitative and quantitative types of study differ in the type of data that they gather. Qualitative usability studies are focused on gaining in-depth understanding based on narrative data, while quantitative studies collect numerical data in order to produce statistically relevant metrics. A qualitative study will uncover usability issues and identify why users stumble there, whereas quantitative studies will determine the task completion rate, the time-on-task, the users' satisfaction, or other relevant metrics.

A small number of participants is sufficient to provide valuable results in qualitative studies, whereas quantitative studies rely on large numbers of participants in order to provide statistically relevant metrics. How many participants are actually required for a quantitative study is determined by the study parameters, whereas qualitative studies can be run with as few as five participants, according to Nielsen (https://www.nngroup.com/articles/how-many-test-users/).

Both study types are compatible with remote methodologies.