Many of us are familiar with standards of rigor associated with sound quantitative research: validity, generalizability, reliability, and objectivity. In fact, researchers take strides, like random sampling and use of treatment and control groups, to ensure such criteria are met. Yet in the qualitative world, notions like validity and reliability often take on new forms.
Good researchers have to be careful not to inflict or project one set of traditional meanings onto another. You cannot analyze qualitative research by quantitative standards, even though faux comparisons happen all around us! (Think about the comical comparisons made between cats and dogs. Often, a cat is criticized for lacking canine qualities like loyalty or pack mentality. Or a dog is chided for not possessing a feline prowess, like the know-how to use a litter box. Even the phrase, “My dog thinks she’s a cat,” is laden with erroneous assumptions.)
What’s meant by qualitative standards of rigor? Mayan, author of Essentials of Qualitative Inquiry, says achieving rigor in qualitative research is not about reproducing quantitative standards. Rather, rigor is about making certain that the qualitative process and outcomes emulate participants’ lived experiences.
Guba and Lincoln (1981) and Lincoln and Guba (1985) gave qualitative rigor a name: trustworthiness. Further, they addressed the kinds of questions qualitative researchers should be thinking about when contemplating trustworthy designs:
Problems of rigor arise from the inquirer’s need to persuade other inquirers or audiences of the authenticity of the information provided and the interpretations that are drawn from it. How can one tell whether the information and interpretations are correct? Whether the information has purely local significance or might have meaning in many situations? Whether it will be found consistently? Whether the interpretations are free from the particular biases of the inquirer? (Guba & Lincoln, 1981, p. 87)
Recognizing that quantitative standards do not apply to qualitative inquiry, Guba and Lincoln advanced four perspectives that work together to help researchers arrive at trustworthiness: credibility, transferability, dependability, and confirmability. Not all studies use each of these; methodological scholars have even crafted new trustworthiness tactics. For the purposes of introducing new inquirers to qualitative rigor, we will start by exploring these more basic perspectives.
Credibility or truth value, can be symbolized by a mirror. A qualitative study is credible when it reflects the participants’ lived experiences with a phenomenon. The findings, thus, have to be believable from the participants’ own perspectives. If qualitative findings do not reflect participants’ realities, the study fails to be credible.
Transferability, or applicability, can be represented by a map. A qualitative study is transferable when the reader can extrapolate meanings that may be applied to other contexts. Transferability has overlaps with generalizability, but retains separate characteristics; as Merriam and Tidsell (2016) conjectured, transferability “...involves leaving the extent to which a study’s findings apply to other situations up to the people in those situations” (p. 256). As with a map, the user has to discover their ultimate destination.
Dependability, or consistency, can be represented by the geyser known as Old Faithful. A good qualitative researcher must ask whether the results of a study were faithful to the data that were collected, particularly when the context is ever-changing. Dependability is not about a study’s replicability; recall, qualitative research is iterative and context-specific. Rather, dependability assures “that, given the data collected, the results make sense” (Merriam & Tisdell, p. 251).
Confirmability, or neutrality, can be represented by an interaction between colleagues in which one checks, or corroborates, the other. We apply confirmability during the final stages of research, asking ourselves whether the results can be confirmed, or corroborated, by other researchers. Confirmability helps assure the inquiry does not reflect researcher bias, motivation, or interest. This does not mean that the researcher seeks out a like-minded colleague; many scholars deliberately choose individuals whose experience and frameworks may differ. Whereas credibility is evaluated by the participants in the study, confirmability is achieved through outside corroboration.