Social desirability bias is a type of bias that can commonly occur with any type of self-reported data. It refers to the tendency of a person, whether consciously or not, to respond to questions with answers that they perceive or expect will be received in a positive way. This bias is especially prevalent in research that asks individuals about behaviors or attitudes or sensitive issues in general, such as drug or alcohol use or frequency of exercise. People may overreport perceived-positive behaviors (eg, claiming to get more exercise than they actually get) or underreport perceived-negative behaviors (eg, saying they smoke less often than they actually do). Perception is key: a behavior such as masturbation or sexual intercourse may be overreported in some contexts and underreported in others.
Deeper dive
Social desirability bias can also occur with reporting diagnoses or conditions, particularly if the condition is one associated with stigma. For example, an epilepsy diagnosis has been stigmatized in some communities or may lead to restriction of privileges, such as loss of a driving license. Studies that rely on self-reported data about epilepsy prevalence may therefore end up with underreporting, depending on the circumstances and the way the question is asked. Other topics with a higher risk of social desirability bias include the following: any sexual activity, use of illicit or restricted substances, self-assessed abilities or skills, personality traits, healthy habits (brushing teeth, flossing, fruit and vegetable consumption, etc.), feelings/emotions, mental health, medication or treatment compliance, excretory activity, intelligence, involvement in or experience of violence, religion, patriotism, bigotry and self-perception/self-esteem (among many others).
Researchers attempt to reduce social desirability bias through several strategies: careful and neutral phrasing of their questions; use of interviewers or interview situations that increase an individual’s comfort level or increase their likelihood of being candid; offering confidentiality and/or anonymity; and collecting data without a person (such as computer-based questions). It may not be possible to completely eliminate the risk of social desirability bias in some research.