Comparing response behaviours between face-to-face and self-completion modes

The COVID-19 pandemic disrupted the European Social Survey (ESS) Round 10 data collection, initially planned for late 2020 and early 2021. Due to pandemic related restrictions, some countries were forced to adopt self-completion modes instead of conducting face-to-face interviews. 

This shift created a natural experiment, enabling the comparison of response behaviours across different survey modes. One study conducted by Piotr Jabkowski (Adam Mickiewicz University) and Marek Muszynski (Polish Academy of Sciences) capitalised on this opportunity to analyse response patterns, such as satisficing and response styles in ESS rounds 9, 10, and 11. 

This considered responses to the face-to-face mode in all countries during Round 9 (2018/19), with Round 10, when around a quarter of the countries switched to self-completion. This is further compared to Round 11 (2023/24), when all countries returned to conducting in-person interviews. 

The speakers employed Bayesian multilevel regression models to examine cross-mode response behaviours. Outcome variables included non-differentiation indices and measures of response styles (extreme, midpoint, and acquiescent), with survey mode as moderator. The findings indicate that respondents in self-completion modes exhibit more non-differentiation and fewer acquiescent and midpoint responses than in face-to-face modes, but yield more extreme responses. 

These differences are more pronounced with 11-compared to 5-point rating scales. The findings are significant for designing mixed-mode international surveys and theoretical understanding of mode differences in response behaviours. 

The results are particularly important as the ESS moves from face-to-face data collection to only self-completion modes over the next two rounds.