Experiences with mixed-mode surveys in times of COVID-19 at Statistics Netherlands

Statistics Netherlands’ social surveys are based on a sequential mixed-mode data collection approach using web, telephone, and face-to-face interviewing. This article illustrates how Statistics Netherlands addressed the sudden, unforeseen loss of face-to-face interviews in social surveys amidst the COVID-19 pandemic.

At the beginning of the pandemic, survey processes were immediately adjusted in several ways to mitigate the negative effects of respondent attrition. Where possible, sampled people initially assigned to face-to-face interviewing were motivated to respond through web or telephone to minimize the loss of response. At the same time regression analysis and simulation were conducted to obtain quantitative insight into the effects of losing face-to-face responses in the sequential mixed-mode designs.

Furthermore, alternative model-based estimation procedures based on structural time series models were implemented to compensate for the bias that is a result of the loss of face-to-face responses. These initiatives are illustrated with applications to the Dutch Labor Force Survey, the Housing Survey, and the Health Survey.