Trap questions (also known as bogus questions) are designed to check whether respondents are cheating by speeding up their completion of the survey. Respondents are thus occasionally asked a trivial question (e.g. to choose a certain answer in a question added for this purpose). If the respondent chooses an incorrect answer, then it can be assumed that they have not paid attention to the content of the question.
The use of trap questions is recommended in the case of panels or in the case of rewards for completing a survey, where the respondent only wants to satisfy the needs of the interviewer by answering quickly or by choosing random answers. It is recommended that these questions are not too difficult, boring, unusual or even offensive.
A study by Baker – Prewitt and Miller (2009) shows that more than 10 % of the respondents are not successful at passing such questions. This research also shows that we can increase the quality of the research by using trap questions:
- respondents use more time to finish the survey;
- fewer respondents speed through the survey;
- fewer respondents choose the same answer at different questions (straight-lining);
- the smaller likelihood for respondents to miss the next trap question;
- less mind cheating;
- respondent’s answers show a higher correlation with the measurement scale.
Respondents' attention can also be enhanced by using a combination of positive and negative statements, which can encourage respondents to read and think more carefully before responding to each statement.