Summary
Two parallel forms of a questionnaire were individually administered to 20 adult male heroin users, administrations being separated by 10–14 days. The first questionnaire was administered by a locally-known heroin user; the second questionnaire was administered by a ‘straight’ interviewer. The two forms were presented as belonging to two separate studies and as having no connection. Subjects consistently presented themselves as heavier users and as being more ‘addicted‘, when interviewed by the straight interviewer than by the known user. In addition, whilst there was no interviewer effect on a short scale of external attributions, scores on a scale of internal attributions were substantially modified between the two interviewers. For the most part, the differences found were substantial, and clear-cut. It is apparent that the heroin users in this study presented themselves in markedly different ways to the two interviewers.