Validity and Reliability

For her last lesson Maxine asks Jonathan to think about trustworthiness. How will the program team know if the results from the qualitative study, using the data collection methods Jonathan selected, can be trusted?

In quantitative research, validity is “the extent to which a measure actually measures what it is intended to measure,” (Rossi 436). However, as Denzin & Lincoln explain, “validity in qualitative research has to do with description and explanation and whether or not the explanation fits the description,” (Denzin & Lincoln, 393). Lincoln and Guba created standards of quality and verification on which to evaluate the trustworthiness of qualitative research, which parallel standards for quantitative research (validity, reliability, objectivity, and external validity/generalizability) (Lincoln and Guba, 1985).

Standars of Quality and Verification

• Confirmability: the degree to which the findings and conclusions can be corroborated or confirmed by others
• Dependability: the degree to which findings and conclusions are consistent and could be repeated
• Transferability: the degree to which the findings and conclusions can be transferred to other contexts or settings
• Credibility: the degree to which the findings and conclusions are credible or believable from the participants’ perspective.

There are several common strategies used by qualitative researchers to enhance the validity of study findings. It is generally recommended that at least 2 of the strategies listed below are incorporated into any qualitative study (Creswell 209).

• Thick, rich description. Inclusion of detailed, written narrative used to provide as much textual imagery as possible so that readers will be able to clearly see how conclusions were drawn
• Triangulation. Examination of multiple and different sources, methods, theories to show convergence within and across the data or help to explain divergence in the findings.
• Extensive quotations. Inclusion of direct quotes from participants that support findings and conclusions
• External audits. Examination of the study design and product by an external agent(s) or researcher to determine whether or not the findings, interpretation, and conclusions are supported by the data.
• Peer review or debriefing. Review of research process by other researchers who ask questions about methods, meanings, and interpretations. This strategy is analogous to interrater reliability.
• Member check. Review and comment on the accuracy of the findings by the participants themselves.