Do interviewers manipulate responses to filter questions? : evidence from a multilevel approach

Abstract

This study provides a theoretically guided analysis of how interviewers might manipulate responses to filter questions (‘triggering rate’) in survey interviews. Drawing on principal-agent theory, we examined how the triggering rate varies by survey mode and across interviewers’ experience with the survey. Using data from a German survey and multilevel models, we find that interviewers do influence filter questions. Most intriguingly, there is an interaction between mode and experience: with increasing experience interviewers in CATI mode (higher monitoring and hourly payment) tend to collect more positive answers to the filter questions, while interviewers in CAPI mode (lower monitoring and case-based payment) tend to collect fewer. Our results suggest that manipulative interview behavior regarding questionnaire filtering exists and varies across incentive structures.