Social desirability bias

Social desirability bias is a social science research term that describes a type of response bias that is the tendency of survey respondents to answer questions in a manner that will be viewed favorably by others. It can take the form of over-reporting "good behavior" or under-reporting "bad", or undesirable behavior. The tendency poses a serious problem with conducting research with self-reports, especially questionnaires. This bias interferes with the interpretation of average tendencies as well as individual differences.

Topics where socially desirable responding (SDR) is of special concern are self-reports of abilities, personality, sexual behavior, and drug use. When confronted with the question "How often do you masturbate?", for example, respondents may be pressured by the societal taboo against masturbation, and either under-report the frequency or avoid answering the question. Therefore, the mean rates of masturbation derived from self-report surveys are likely to be severe underestimates.

When confronted with the question, "Do you use drugs/illicit substances?" the respondent may be influenced by the fact that controlled substances, including the more commonly used marijuana, are generally illegal. Respondents may feel pressured to deny any drug use or rationalize it, e.g. "I only smoke marijuana when my friends are around." The bias can also influence reports of number of sexual partners. In fact, the bias may operate in opposite directions for different subgroups: Whereas men tend to inflate the numbers, women tend to underestimate theirs. In either case, the mean reports from both groups are likely to be distorted by social desirability bias.

Other topics that are sensitive to social desirability bias:

The fact that people differ in their tendency to engage in socially desirable responding (SDR) is a special concern to those measuring individual differences with self-reports. Individual differences in SDR make it difficult to distinguish those people with good traits who are responding factually from those distorting their answers in a positive direction.

When SDR cannot be eliminated, researchers may resort to evaluating the tendency and then control for it. A separate SDR measure must be administered together with the primary measure (test or interview) aimed at the subject matter of the research/investigation.The key assumption is that respondents who answer in a socially desirable manner on that scale are also responding desirably to all self-reports throughout the study.

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