Qualitative research includes which of the following?

Qualitative research focuses on exploring and understanding human experiences, behaviors, and social phenomena through non-numerical data. It seeks to gain insights into individuals' perspectives and the meanings they ascribe to their experiences. Case studies and participant observations are fundamental methods in qualitative research, allowing researchers to gather deep, contextualized information in natural settings.

Through case studies, researchers can examine in-depth a particular instance or phenomenon, which helps to capture the complexity of human behavior. Participant observations provide a way for researchers to immerse themselves in a setting, enabling them to observe interactions and contexts that quantitative methods might overlook. These approaches are particularly beneficial in fields such as healthcare, where understanding the nuances of patient experiences and clinician interactions is crucial for improving care.

In contrast, the other options list methodologies that are primarily quantitative in nature, focusing on numerical data, statistical analysis, and experimental design, which do not align with the core objectives and methods of qualitative research.