Validity, reliability, and readability of single-item and short physical activity questionnaires for use in surveillance: A systematic review.

This review identified a variety of brief PAQs, but most of them were evaluated in only a single study. Validity and reliability of short and long questionnaires are found to be at a comparable level, short PAQs can be recommended for use in surveillance systems. However, the methods used to assess measurement properties varied widely across studies, limiting the comparability between different PAQs and making it challenging to identify a single tool as the most suitable. None of the evaluated brief PAQs allowed for the measurement of whether a person fulfills current WHO physical activity guidelines. Future development or adaptation of PAQs should prioritize readability as an important factor to enhance their usability.