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Online interviews 2: Purposive sampling and digital divides

Ten years ago, the “predicted trajectory of future penetration” of the Internet generated optimism on behalf of online research (Couper 2000). The rise of the Internet as a pervasive communication technology heralded unprecedented reach and ever lower costs of social science.

This second post on conducting qualitative interviews online is concerned with exactly this reach - the recruitment of respondents. Borrowing from quantitative lingo, one might call it sampling. But it should be made clear that theoretical purpose rather than probability must guide the choice of who to interview. Thus, I suggest the term 'purposive sampling'.

A major obstacle to purposive sampling of interviewees for online questioning is the so-called digital divide. The divide exists both between Internet users and non-users, and within the flock of Internet users.

According to Couper’s early meta-study, between 27-53% of adult Americans used the Internet in 1998-99. A recent US survey said the figure was now 74%, with growth in penetration flattening out since 2006 (Rainie 2010). To put that into perspective, the 74% is dwarfed by the 83% who claimed to own a cell phone.

Although not directly comparable, these figures suggest that using online methods reduces the number of people that can be accessed. This is termed coverage error in quantitative research. In qualitative research it means that the people needed to inform the research are simply not reachable via the Internet.

This is extra problematic, because Internet access is clearly associated with social stratification. Even without confronting the digital divide between the global North and the global South, there are major domestic discrepancies between Internet users and non-users. To put it crudely, Internet users tend to be too white, too well off and too educated to be representative of the population as a whole.

Apart from simple access, lack of skills can also be a barrier to participation in online interviews. For example, something as fundamental as literacy is a potential issue when conducting interviews in a text-based environment.

Another related issue is technological constraints. Owning and using a computer does not mean that it has the required hardware or can run the software necessary for conducting interviews. This is a real threat, and a reason for choosing text-based interviewing over voice or video technology.

A final issue that even recent textbooks seem to underestimate is the fact that online communication might be subject to easy wire-tapping. This could intimidate vulnerable respondents. Another security-related problem is that recruitment might be hindered by the lack of accessible directories of online contact details.

The next post in the mini series on online interviews deals in more detail with the case of interviewing through text as opposed to speech.

Couper, M. P. (2000). Web surveys: A Review of Issues and Approaches. The Public Opinion Quarterly , 64 (4), 464-494.

Rainie, L. (2010). Internet, broadband, and cell phone statistics. Pew Internet & American Life Project. Washington, DC: Pew Research Center.