Mixed mode designs are increasingly important in surveys and large longitudinal studies are progressively moving to or considering such a design. In this context our knowledge regarding the impact of mixing modes on data quality indicators in longitudinal studies is sparse. This study tries to...

The quasi-simplex model makes use of at least three repeated measures of the same variable to estimate its reliability. The model has rather strict assumptions about how various parameters in the model are related to each other. Previous studies have outlined how several of the assumptions of...

It is common practice to adapt the format of a question to the mode of data collection. Multi-coded questions in self-completion and face-to-face modes tend to be transformed for telephone into a series of 'yes/no' questions. Questions with response scales are often branched in telephone...

We assess whether the probability of a sample member participating at a particular wave of a panel survey is greater if the same interviewer is deployed as at the previous wave. Previous research on this topic mainly uses non-experimental data. Consequently, a) interviewer change is generally...