Convenience sampling is a type of sampling by which the researcher selects a study environment and/or study participants primarily based on ease of access, availability, and/or familiarity. Convenience sampling is not uncommon in qualitative research when researchers may need to complete their research in a short time frame and at a relatively low cost. For example, an ethnographer who wants to study how people behave in a confined space might design her research to observe people on her daily commute on the local subway. Or a graduate student might select clergy within a narrow radius of his university to conduct in-depth interviews to understand the roles clergy play in the lives of their congregations. Or focus group discussions might be conducted at a geriatric facility where the researcher visits her parents in order to learn about skilled nursing care.
In each case, the researcher may come away with insightful information about people in confined spaces on that particular subway car on a particular day, or clergy roles among the particular clergy drawn from religious groups within the neighborhood, or skilled nursing care at that particular geriatric facility. However, the important limitation of these studies lies in the fact that the subway car, the religious groups, and the geriatric facility were not selected because they were somehow representative of confined spaces, religious organizations, or senior medical care facilities, but rather because these locations and participants were in easy access and familiar to the researchers. As a result, and without other research to help triangulate the data, the researcher (and users of the research) have no way of knowing how (or if) the particular subway car on the particular day and time of day, or the clergy in the neighborhood, or the geriatric facility where the researcher’s parents live relate to (i.e., is the same or different than) the broader context of confined spaces, religious organizations, or geriatric facilities.
This raises an important limitation to convenience sampling. From a quality standpoint, convenience sampling limits the ultimate usefulness of a qualitative study because the data based on a convenience sample do not allow the researcher (and users of the research) to apply the findings to other contexts, i.e., convenience sampling limits the transferability of the research. Transferability is a vital aspect of the Total Quality Framework Transparency component and is fundamental to contributing something of value. And in the end, contributing something of value – that is, maximizing the usefulness of the research – is the researcher’s ultimate goal.
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