Questionnaire design

Questionnaire design is the process of writing and structuring survey questions and their response options so that they measure what they intend to measure, reliably and without steering respondents toward a particular answer. It covers question wording, question order, and the format of response options, such as open text, multiple choice, or a likert scale.

Well-known pitfalls include leading questions that suggest a preferred answer, double-barreled questions that ask about two things at once but allow only one response, and acquiescence bias, where respondents tend to agree with whatever statement they are shown regardless of content. Question order matters too: earlier questions can prime how respondents think about later ones, and where a sensitive question sits in a questionnaire can affect both willingness to answer it and the response rate for the rest of the survey. This differs from sampling frame design, which determines who is asked, while questionnaire design determines what they are asked and how.

Good questionnaire design is usually validated through cognitive interviewing or pilot testing before fielding a survey at scale, and it interacts with survey mode effects: the same question can perform differently read aloud by an interviewer than read silently on a screen. Poor questionnaire design cannot be fully corrected after the fact by survey weighting or other statistical adjustment, since weighting corrects who responded, not how a flawed question was answered.