Interviews involve a social relationship between two persons. Respondents adjust their conduct to what they consider to be appropriate to the situation. Interviewers whether they like to or not, will be cast into some role by respondents. Interviewers must be conscious of the alternative roles at their disposal and attempt to establish the role which will best further the purposes of their study.
When interviewing takes place on a subject about which there is some expectation regarding social approval or disapproval, or in which there is a strong ego involvement, respondents err by idealizing their behavior. Low-income respondents, in particular tend to give the kinds of answers they think that society through the interviewer, wants to hear. In interviews among blacks, white interviewers obtain significantly higher proportions of what may be called ‘proper’ or ‘acceptable’ answers than do black interviewers. Middle-class interviewers find more conservative attitudes among lower income groups than do working class interviewers. The greater the social distance between the interviewers and the respondents, the greater the likelihood of bias. Respondents are used to talking about personal experiences only to listeners who share a great deal of experience and symbolism with them and with whom they can safely assume that words and gestures are assigned similar meanings. But in the interview these assumptions break down.
Age, race, and income of the interviewer all tend to influence the responses obtained from personal interviews. Age and race are not so apparent in telephone interviews and can be expected to have less influence in that method of communication. Older interviewers are perceived as authority figures and responses are modified accordingly. Black interviewers with white respondents or the opposite cause some tension. In each combination the respondent tends to answer in a way that will be least apt to have racial implications. Interviewers who have higher incomes themselves tend to find higher incomes among respondents.
In view of the evidence showing the influence of age, race, and income of the interviewer on information obtained, extensive efforts to control these are made by good researchers. Unfortunately, the composition of the field staff can usually be modified only slightly for individual studies. Typically, the same interviewers are used to do many different kinds of projects; they work by assignment and interview all types of respondents. Most interviewers are middle aged middle class women, while respondents are drawn from all classes. There is no relatively simple and economical way of matching interviewer and respondents nor of correcting for the biasing effect of given interviewer characteristics.
A basic condition for optimum communication is that respondents perceive interviewers as people who are likely to understand and accept them and what they have to say. Interviewers must be perceived as ‘within range’ – that is, they must be seen as people to whom the respondents’ statements and experience will not be foreign of offensive. This does not, mean that respondents need to see interviewers as similar to themselves; but they must view interviewers as capable of understanding their points of view and of doing so without rejecting them.
In general, the more characteristics interviewers and respondents have in common, the greater the probability of a successful interview. An economically feasible method of achieving this pairing has not been developed.
Not only can interviewers bias survey results by their impact on the respondents but they may influence results by the way they react to respondents. Differences in the characteristics of interviewers, such as experience attitudes, and opinions also affect the recorded answers.