定性研究
Qualitative research is not without limitations. These limitations include participant reactivity, the potential for a qualitative investigator to over-identify with one or more study participants, "the impracticality of the Glaser-Strauss idea that hypotheses arise from data unsullied by prior expectations," the inadequacy of qualitative research for testing cause-effect hypotheses, and the Baconian character of qualitative research. Participant reactivity refers to the fact that people often behave differently when they know they are being observed. Over-identifying with participants refers to a sympathetic investigator studying a group of people and ascribing, more than is warranted, a virtue or some other characteristic to one or more participants. Compared to qualitative research, experimental research and certain types of nonexperimental research (e.g., prospective studies), although not perfect, are better means for drawing cause-effect conclusions.