ABSTRACT
Introduction At the centre of a comparative research study is the work of collecting, recording and analysing data. Researchers tend to have a preference for particular methods, in part because these methods are suited to the subject and type of questions studied in their discipline. Yet there are many different methods that a health services researcher can use, even if they are working within traditional disciplinary boundaries. One example is the greater use being made by experimental medical researchers of interviews with patients to gather data about the patients' perceptions of outcomes, as well as using the more traditional objective measures of physiological and functional outcome. Health researchers making comparisons are even more likely to use a variety of methods. This is especially so if they are examining the context of the items they are comparing, where they often need to gain data about lifestyle, or social, economic and political factors.
