It is increasingly argued that qualitative approaches have an important role in health care research. A wide range of methods are used to collect qualitative data, including in-depth interviews, focus groups and observational methods such as participant observation. The reliability and validity of qualitative studies can be addressed by a variety of techniques. Although there is less consensus about appropriate methods of analysing qualitative data, such analyses tend to be grounded in the data, and involve iterative procedures and the development and refinement of typologies, analogies and other forms of concept to make sense of data.