Questionnaire designers use readability measures to ensure that questions can be understood by the target population. The most common measure is the Flesch-Kincaid Grade level, but other formulas exist. This article compares six different readability measures across 150 questions in a self-administered questionnaire, finding notable variation in…

There is some evidence that a scrolling design may reduce breakoffs in mobile web surveys compared to a paging design, but there is little empirical evidence to guide the choice of the optimal number of items per page. We investigate the effect of the number of items presented on a page on data quality in two types of questionnaires: with or…