RESEARCH METHOD COHEN ok

150 VALIDITY AND RELIABILITY
Validity and reliability in interviews
In interviews, inferences about validity are made
too often on the basis of face validity (Cannell
and Kahn 1968), that is, whether the questions
asked look as if they are measuring what they
claim to measure. One cause of invalidity is bias,
defined as ‘a systematic or persistent tendency
to make errors in the same direction, that is,
to overstate or understate the ‘‘true value’’ of
an attribute’ (Lansing et al. 1961). One way of
validating interview measures is to compare the
interview measure with another measure that has
already been shown to be valid. This kind of
comparison is known as ‘convergent validity’. If
the two measures agree, it can be assumed that the
validity of the interview is comparable with the
proven validity of the other measure.
Perhaps the most practical way of achieving
greater validity is to minimize the amount
of bias as much as possible. The sources of
bias are the characteristics of the interviewer,
the characteristics of the respondent, and the
substantive content of the questions. More
particularly, these will include:
the attitudes, opinions and expectations of the
interviewer
a tendency for the interviewer to see the
respondent in his or her own image
atendencyfortheinterviewertoseekanswers
that support preconceived notions
misperceptions on the part of the interviewer
of what the respondent is saying
misunderstandings on the part of the
respondent of what is being asked.
Studies have also shown that race, religion,
gender, sexual orientation, status, social class and
age in certain contexts can be potent sources of
bias, i.e. interviewer effects (Lee 1993; Scheurich
1995). Interviewers and interviewees alike bring
their own, often unconscious, experiential and
biographical baggage with them into the interview
situation. Indeed Hitchcock and Hughes (1989)
argue that because interviews are interpersonal,
humans interacting with humans, it is inevitable
that the researcher will have some influence on
the interviewee and, thereby, on the data. Fielding
and Fielding (1986: 12) make the telling comment
that even the most sophisticated surveys only
manipulate data that at some time had to be
gained by asking people! Interviewer neutrality is
a chimera (Denscombe 1995).
Lee (1993) indicates the problems of conducting
interviews perhaps at their sharpest, where the
researcher is researching sensitive subjects, i.e.
research that might pose a significant threat
to those involved (be they interviewers or
interviewees). Here the interview might be seen as
an intrusion into private worlds, or the interviewer
might be regarded as someone who can impose
sanctions on the interviewee, or as someone who
can exploit the powerless; the interviewee is in the
searchlight that is being held by the interviewer
(see also Scheurich 1995). Indeed Gadd (2004)
reports that an interviewee may reduce his or
her willingness to ‘open up’ to an interviewer
if the dynamics of the interview situation are
too threatening, taking the role of the ‘defended
subject’. The issues also embrace transference and
counter-transference, which have their basis in
psychoanalysis. In transference the interviewees
project onto the interviewer their feelings, fears,
desires, needs and attitudes that derive from their
own experiences (Scheurich 1995). In countertransference
the process is reversed.
One way of controlling for reliability is
to have a highly structured interview, with
the same format and sequence of words and
questions for each respondent (Silverman 1993),
though Scheurich (1995: 241–9) suggests that
this is to misread the infinite complexity and
open-endedness of social interaction. Controlling
the wording is no guarantee of controlling the
interview. Oppenheim (1992: 147) argues that
wording is a particularly important factor in
attitudinal questions rather than factual questions.
He suggests that changes in wording, context
and emphasis undermine reliability, because
it ceases to be the same question for each
respondent. Indeed he argues that error and
bias can stem from alterations to wording,
procedure, sequence, recording and rapport, and
that training for interviewers is essential to