Questionnaire construction refers to the design of a questionnaire to gather statistically useful information about a given topic. When properly constructed and responsibly administered, questionnaires can provide valuable data about any given subject.

Questionnaires are frequently used in quantitative marketing research and social research. They are a valuable method of collecting a wide range of information from a large number of individuals, often referred to as respondents.

What is often referred to as "adequate questionnaire construction" is critical to the success of a survey. Inappropriate questions, incorrect ordering of questions, incorrect scaling, or a bad questionnaire format can make the survey results valueless, as they may not accurately reflect the views and opinions of the participants.

Different methods can be useful for checking a questionnaire and making sure it is accurately capturing the intended information. Initial advice may include:

Empirical tests also provide insight into the quality of the questionnaire. This can be done by:

In the realm of psychological testing and questionnaires, an individual task or question is referred to as a test Item or item. These items serve as fundamental components within questionnaire and psychological tests, often tied to a specific latent psychological construct (see operationalization). Each item produces a value, typically a raw score, which can be aggregated across all items to generate a composite score for the measured trait.

Test items generally encompass three primary components:

The degree of standardization varies, ranging from strictly prescribed questions with predetermined answers to open-ended questions with subjective evaluation criteria.