Quality in unimode and mixed-mode designs: a multitrait-multimethod approach

"So far, most surveys used face-to-face or telephone questionnaires in order to collect data. But the costs of achieving a survey using these traditional modes increase. At the same time, the response rates decrease, making the idea of switching mode very attractive. Because each mode has its own weaknesses and strengths, the idea of mixing modes of data collection is becoming more and more popular. Nevertheless, combining different modes of data collection may be problematic if people answer differently depending on the mode. Also, a switch from a unimode to a mixed-mode design may threaten t... Mehr ...