Qualitative research has been defined as "any data-gathering technique that generates narrative data (ie words) rather than numerical data (numbers)."1 The purpose of qualitative research is description/theory building, and there are fewer controls than in quantitative research. Interviewing and focus group discussions are ways to obtain qualitative data, and case studies are considered qualitative research.

Limitations of qualitative research include limited reliability (generalizability), and difficulty in making comparisons between qualitative studies. Also, the person collecting qualitative data must be well trained in interviewing technique to avoid bias.

1 Achterberg, CL and Shepherd, SK. The comonents and use of qualitative research. In Research: Successful Approaches, ER Monsen, Ed.Chicago: ADA, 1992.