Question Characteristics and Interviewer Effects
Thomas W. Mangione, Floyd J. Fowler, Jr., and Thomas A. Louis
As part of a large study of how interviewers affect data, this paper reports the results of analyses of how question characteristics affect the likelihood that interviewers will influence survey responses.
It was found that ratings of the sensitivity and difficulty of questions were not significantly related to interviewer effects as measured by the intraclass correlation. Whether questions pertained to objective or subjective topics and whether they called for open-ended or fixed responses also were unrelated to interviewer effects. However, it was found that interviewer effects were directly related to the rate at which interviewers had to use follow-up probes in order to obtain an adequate answer. Questions prone to recording errors were also more likely to be affected by interviewers.
The results imply that, during the pretesting phase of a project, questions should be evaluated to identify those that routinely require follow-up probes and redesigned to minimize the need for interviewer initiative to obtain adequate answers.
Survey questions; interviewer effects; survey methods.