Privacy: bad for your health?

In reply: In a world in which people are increasingly busy and mobile, increasingly concerned about invasions of privacy and increasingly approached to participate in surveys, survey response rates that could be readily achieved 25 years ago are now very much more difficult to attain. High response rates (ie, 60% and over) are still very desirable and can still be achieved. We have conducted surveys on sensitive issues, such as drug-taking, and achieved response rates that would probably satisfy even Arnolda. But this requires very intensive field activity that is not always justified by the nature of the project.

The survey in question was not a health survey. It set out to provide general background information, exploring comparative levels of concern about, and the relationships between, a very wide range of privacy issues on a scale adequate to allow relatively small groups within the population to be examined. It was not intended to yield precise and critical measurements. Measures of “concern” or “reluctance” are highly context-dependent, “soft” measures, subject to interpretation, both by the respondents and by end-users. External validity is therefore not the issue: a response rate of 80% would not have made the figures demonstrably more “accurate”. Given the imprecise nature of the measures obtained, overengineering the sample relative to other components of the survey design would have been a waste of (public) money, better devoted to further research. The survey was part of a wider-ranging project and was planned in close consultation with the Office of the Privacy Commissioner in the light of their needs and priorities.

It is appropriate that this issue arose out of a debate on privacy. As privacy constraints bite harder, whether imposed by statute or codes of practice, or arising through increasing resistance from subjects, medical researchers are going to have to come to terms with problems of non-response in the same way that social-survey researchers have.