Mixed-Mode and Mixed-Device Surveys

Abstract

Online surveys are one of the most prominent data collection methods in Europe and the USA. Not only are they fast and cheap, data quality in well-designed online surveys is high, especially when sensitive questions are asked. Disadvantages are the threat of undercoverage, as not everyone has Internet access, and high nonresponse. In order to overcome these disadvantages, mixed-mode designs are used in which multiple data collection methods are combined. The strength of mixed-mode surveys is their potential to reduce coverage and nonresponse error at affordable costs. However, survey modes may differ in the effect they have on measurement error, and one critical question is how data from different modes may be combined. A special form of mixed mode design is a mixed-device survey. Web surveys are increasingly completed on a range of different devices. Mobile phones, tablets, and even smart watches are being used in addition to regular desktop PCs. The question arises whether or not answers obtained via smartphones or tablets are comparable to answers via regular desktop PCs. Screen sizes are very different and also the mode of response entry varies between devices. Survey software increasingly adapts to mobile survey responding via responsive survey design. The software detects the device used for completing the survey and adapts the format accordingly. This chapter discusses the most common designs for mixed mode surveys and summarizes the empirical evidence for reducing coverage and nonresponse error and then focuses on measurement error. We pay special attention to careful design and provide rules for doing web surveys that are in fact mixed-device surveys.