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. 2021 Jan;43(1):86-88.
doi: 10.1177/0253717620977000. Epub 2020 Dec 17.

The Inconvenient Truth About Convenience and Purposive Samples

Chittaranjan Andrade  1
Affiliations

The Inconvenient Truth About Convenience and Purposive Samples

Chittaranjan Andrade. Indian J Psychol Med. 2021 Jan.

Abstract

Most research is conducted on convenience and purposive samples that may be randomly or nonrandomly drawn. A convenience sample is the one that is drawn from a source that is conveniently accessible to the researcher. A purposive sample is the one whose characteristics are defined for a purpose that is relevant to the study. The findings of a study based on convenience and purposive sampling can only be generalized to the (sub)population from which the sample is drawn and not to the entire population. This article explains the concepts involved with the help of examples of both good and bad sampling practice. Database studies and studies with enriched designs are cited as special examples of convenience and purposive sampling. Issues related to the internal and external validity of convenience and purposive samples are explained. The importance of good sampling techniques in the design and interpretation of research is understated; this must change.

Keywords: Convenience sampling; database studies; enriched samples; external validity; internal validity; purposive sampling.

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Conflict of interest statement

The author declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

References

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