Qualitative Research: The Evaluation of its Credibility, Fittingness, and Auditability
Until recently, the dominant paradigm in nursing espoused the use of quantitative research methodologies. With the advancing paradigm shift in the discipline of nursing, qualitative research is gaining acceptance as a legitimate mode of inquiry. Nurse scholars are embracing both quantitative and qualitative methods of inquiry in order to investigate the whole of nursing; that is, the whole of human experience. Quantiative and qualitative research methodologies complement each other. Qualitative research is needed to identify the characteristics of phenomena; quantitative research is needed to control phenomena and to predict outcomes of nursing interventions. Nurse researchers have tried to judge the rigor of qualitative research, using the criteria for quantitative studies. Because qualitative inquiry is based on completely different assumptions than are quantiative methods, another set of criteria is needed to evaluate this research. The identification of criteria appropriate for the evaluation of qualitative studies should remove one obstacle to the acceptance of this method of inquiry for nursing research. Burns (1989) proposed five standards for critiquing qualitative research: descrptive vividness, methodological congruence, analytic preciseness, theoretical correctedness, and hueristic relevance. Sandelowski (1986) addressed criteria of rigor in scientific inquiry, based on Guba and Lincoln's (1981) factors of truth value, applicability, consistency, and neutrality. According to Guba and Lincoln, credibility is the proposed criterion against which truth value of a qualitative study should be judged. Fittingness is the criterion that has been suggested, against which the applicability of qualitative studies should be evaluated. Auditability is the suggested criterion for evaluating the consistency of qualitative research, while confirmability is the criterion of neutrality in qualitative studies. These qualitative terms will be related to the conepts of reliability and validity used in quantitative research. Two of the most controversial criteria for evaluating qualitative research - reliability and validity - are the focus of this article. A checklist, which can be used as a guideline for critiquing reliability and validity, has been developed to help in the transition of evaluating these two criteria from the entrenched quantitative criteria to the newly created qualitative criteria. In this article, the quantitative terms of internal validity, external validity, and reliability are referred to as credibility, fittingness, and auditability, respectively. Guba and Lincoln (1981) suggested the renaming of the scientific terms to these naturalistic terms, which are more appropriate to qualitative research.