Research methods are not paradigm specific but should be selected on the basis of whether they fit with the purposes of an investigation. In the postpositivist, interpretive, and critical paradigms, both qualitative and quantitative data or a combination of these may be used without violating paradigm assumptions. Attention to the four basic issues of quality of the data, investigator bias, quality of the research process, and usefulness of the finding is necessary to produce valid research. Although researchers in each paradigm deal with these differently, combining strategies across paradigms may enhance the scientific value of a study and result in new methodologies to address the health needs of all people.