Year 2020, Volume 7 , Issue 1, Pages 73 - 79 2020-04-01

When interviewing: how many is enough?

William W. COBERN [1] , Betty Aj ADAMS [2]

Researchers need to know what is an appropriate sample size for interview work, but how does one decide upon an acceptable number of people to interview? This question is not relevant to case study work where one would typically interview every member of a case, or in situations where it is both desirable and feasible to interview all target population members. However, in much of qualitative and mixed-methods research and evaluation, the researcher can only reasonably interview a subset of the target population. How big or small should that subset be? This paper provides a brief explanation of why the concept of generalization is inappropriate with respect to the findings from qualitative interviewing, what wording to use in place of generalization, and how one should decide on sample size for interviews.
Research methodology, Sample size, Generalization, Interview research, Qualitative research, External validity
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Primary Language en
Subjects Education, Scientific Disciplines
Published Date March
Journal Section Articles

Orcid: 0000-0002-0219-203X
Author: William W. COBERN (Primary Author)
Institution: Western Michigan University
Country: United States

Orcid: 0000-0002-8554-8002
Author: Betty Aj ADAMS
Institution: Western Michigan University
Country: United States

Thanks Here is an example of how this approach might be worded for a research proposal. For this example, we are indebted to our colleague Dr Brandy Pleasants.

Publication Date : April 1, 2020

APA COBERN, W , ADAMS, B . (2020). When interviewing: how many is enough?. International Journal of Assessment Tools in Education , 7 (1) , 73-79 . DOI: 10.21449/ijate.693217