Importance of Measuring and Accounting for Interviewer Effects
Interviewers can vary in demographic attributes (e.g., age, gender), level of perceived experience and professionalism, approach to recruitment and survey administration (e.g., adherence to verbatim question wording), and behavior (e.g., reactions to reluctant respondents). Variability among interviewers can affect response rates, answers to survey questions, and data quality. In addition, interviewer effects can vary among groups of respondents (e.g., larger effects among older respondents compared to younger respondents). Thus, measuring, modeling, and accounting for interviewer effects is a crucial component of large-scale survey-driven studies.
Rising interviewer turnover and difficulties recruiting new interviewers are significantly increasing study costs and threatening the face-to-face interview paradigm used by many large-scale health and aging studies. Multiple organizations and federal agencies have responded with new strategies to improve hiring and retention of interviewers, including shortened hiring processes (i.e., reduced time between initial application and starting work), increased pay, bonuses and incentives, and restructuring of interviewer positions to regular, full-time positions with benefits. The effectiveness of these strategies has been mixed, in part because interviewers vary in their needs (e.g., some prefer full-time employment while others prefer short-term, flexible employment). Moreover, the impact of these strategies likely varies based on labor markets.