Switching a cross-national face-to-face panel survey to alternative data collection modes: Challenges and insights from the Survey of Health, Ageing and Retirement in Europe (SHARE)

The Survey of Health, Ageing and Retirement in Europe (SHARE), like many other surveys, put huge efforts into the realization of an additional COVID-19 survey including a mode switch to telephone interviewing. While this dataset is interesting on its own, it is even more so with regard to its utilization in combination with the wealth of existing panel data from more than 400,000 face-to-face interviews from eight waves of data collection, including life histories of respondents. At the same time, the changes to mode and timing of data collection raise a number of important questions that have not been sufficiently answered yet.

Against this background, we want explore the effects of a mode switch during an ongoing panel survey and in particular for SHARE’s specific target population of people aged 50 years and older. We are primarily interested in two connected research questions: (1) Who does and who does not respond in a certain interview mode (mode selection effect)? (2) How is a question answered in a certain interview mode (mode measurement effect)?

To answer these questions, we focus on data from the eighth wave of SHARE until its suspension in March 2020 and the two waves of the SHARE Corona Telephone Survey (SCS) fielded in summers 2020 and 2021, yielding about 100,000 additional interviews. Based on these data, we analyze potential effects of the introduced changes in data collection with a particular focus on the older population and give practical advice for researchers facing similar challenges in directing their efforts.