IPAQ, GPAQ and Co – How readable are physical activity questionnaires?

Background: Self-report questionnaires are frequently used to monitor physical activity (PA) behavior. There is a considerable amount of research on the measurement properties of questionnaires. However, these studies rarely consider the linguistic characteristics of questionnaires and how those might influence their measurement properties. In other words, not all respondents might understand questionnaires that are difficult to read.

Purpose: The aim of this study is to analyze the readability level of PA questionnaires and assess their adherence to the level recommended by the American Medical Association.

Methods: The analysis included 45 commonly used PA questionnaires. The level of readability was calculated using the Flesch-Kincaid Reading Ease (FKRE) formula.

Results: The calculation of readability levels showed that only five questionnaires reached a mean readability score within the recommended level. 22 questionnaires were classified as ‘fairly easy to read’ or ‘plain English’, and can be understood by those with basic education. The remaining questionnaires contained sentences or words rated as being long and complicated. 18 questionnaires were rated as being ‘fairly difficult to read’ to ‘very difficult to read’ and may require a high-school or college-level education to understand.

Conclusions: The results suggest that most of the PA questionnaires analyzed do not meet recommended readability standards. As a consequence, individuals with lower levels of education might not always understand them. To increase the accuracy of data and improve the measurement properties of PA questionnaires, readability should be considered when constructing questionnaires.

Practical implications: It is recommended to consider linguistic characteristics when developing, testing and translating questionnaires. Strategies for improving questionnaire readability and understandability may include cognitive testing and/or the collaboration with linguists.

Funding: no outside funding