An evaluation of the effect of response formats on data quality in web surveys

When designing a web questionnaire, various HTML input elements can be used to register respondents' answers. Two input elements, radio buttons and drop-down boxes, can be regarded as technically equivalent because they serve the same purpose-both allowing selection of one answer from a list of response options. However, these input elements are dissimilar in many respects, and there is reason to believe that some people are less familiar with drop-down boxes. By means of two experiments, this study evaluates the effect of the two response formats on data quality. Lower data quality was expected in the drop-down boxes condition than in the radio buttons condition. The data showed that a slight preference for radio buttons might be justified, although both response formats have benefits and drawbacks. The choice between these response formats is not self-evident and needs to be guided by other considerations such as sample composition and survey design.