The Context of HIV Risk Among Drug Users and Their Sexual Partners

aggravate self-presentation bias. This evidence, which was culled from a
large number of studies, also suggested that task variables (e.g., the
structure and length of questions and how the interview was
administered) were important factors influencing response, with memory
variables and the characteristics of interviewers and respondents being
much less important.
In a later study, Bradburn and Sudman (1979) attempted to determine
whether more anonymous forms of data collection (self-administered
questionnaire or telephone survey) might reduce response bias relative to
that which occurs when interviews are conducted face-to-face. The
questions included highly undesirable behaviors such as drunken driving
and bankruptcy. While the more anonymous interview did not
consistently increase levels of behavior reported, variations in question
structure and length and structure did. Subjects were randomized to
closed-ended versus open-ended questions, long versus short questions,
and questions with standard versus familiar wording. Familiarly worded
questions are questions that employ language that respondents themselves
would use. The results indicated that long, open-ended, familiarly
worded questions yielded higher levels of reporting than short, closedended
questions with standard wording. The pattern was evident even
when differences in formats were examined on an item-by-item basis.
Very few interactions of formats were noted.
Impact of Questionnaire Format
In the present study, the authors examined the impact of question length
and question order on the extent of underreporting and zero-reporting of
high-risk practices. Without a gold standard against which to validate
self-reports, the authors made the assumption that higher levels of
reported risk behaviors would on average be more accurate since selfreports
are downwardly biased when respondents find questions to be
threatening or to invite socially desirable responses (Catania et al. 1990).
The authors hypothesized that long questions and questions asked late
rather than early in the interview would result in higher levels of
reporting. The long questions (15 words or more) were preceded by
preambles that essentially encouraged respondents to acknowledge
socially undesirable (risk) behavior. For example, the question about
needle sharing was prefaced with the statement, “Now we have some
questions about needles and syringes. There are reasons people share
used outfits, such as being dope sick, not having your own works, and not
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