For several years, the Federal Statistical Office (FSO) has been working on the systematic implementation of questionnaire testing. A pretest laboratory was established in 2007 and complemented by an eye tracker in 2009. Questionnaires of online surveys are now increasingly evaluated by qualitative testing methods and redesigned to reduce the burden for respondents and to increase data quality of official statistics.
Pretesting online questionnaires shall improve their usability, functionality and comprehensibility. At the FSO, a three step approach is applied: Firstly, we observe eye movements and facial expressions (in real-time), while respondents deal with the questionnaire. Secondly, we conduct cognitive interviews, in which we show the video of eye movements during the fill-in process to the probands. By using the methods of retrospective think aloud and probing we try to figure out reasons for incomplete or missing answers. In a third step, we analyse and interpret the eye tracking data (fixation length, number of fixations etc.). As there are benefits from every method on the one hand, each method has its weaknesses, too. Therefore we combine information from the three sources with each other (“triangulation”), to provide higher data quality in terms of more objective results and a richer overall picture.
Eye Trackingcan be a very useful method in pretesting questionnaires, because it delivers insights into the unconscious behaviour of probands. This behaviour also has a strong influence on the answering process and consequently determines data quality. For example the order in which a proband looks at a questionnaire page can hardly be described in words, as the proband doesn’t think actively about it.
Selected examples from three usability-tests, concerning the perception and understanding of navigation, error messages and instructions will underline the benefit of eye tracking in questionnaire testing.