Abstract
BackgroundInterviewers can substantially affect self-reported data. This may be due to random variation in interviewers’ ability to put respondents at ease or in how they frame questions. It may also be due to systematic differences such as social distance between interviewer and respondent (e.g., by age, gender, ethnicity) or different perceptions of what interviewers consider socially desirable responses. Exploration of such variation is limited, especially in stigmatized populations.MethodsWe analyzed data from a randomized controlled trial of HIV self-testing amongst 965 female sex workers (FSWs) in Zambian towns. In the trial, 16 interviewers were randomly assigned to respondents. We used hierarchical regression models to examine how interviewers may both affect responses on more and less sensitive topics, and confound associations between key risk factors and HIV self-test use.ResultsModel variance (ICC) at the interviewer level was over 15% for most topics. ICC was lower for socio-demographic and cognitively simple questions, and highest for sexual behaviour, substance use, violence and psychosocial wellbeing questions. Respondents reported significantly lower socioeconomic status and more sex-work related violence to female interviewers. Not accounting for interviewer identity in regressions predicting HIV self-test behaviour led to coefficients moving from non-significant to significant.ConclusionsWe found substantial interviewer-level effects for prevalence and associational outcomes among Zambian FSWs, particularly for sensitive questions. Our findings highlight the importance of careful training and response monitoring to minimize inter-interviewer variation, of considering social distance when selecting interviewers and of evaluating whether interviewers are driving key findings in self-reported data.Trial registrationclinicaltrials.gov NCT02827240. Registered 11 July 2016.
Highlights
We first ran models that contained fixed effects for study site and random intercepts for Results The Zambian Peer Educators for HIV Self-Testing (ZEST) baseline sample consisted of 965 Female sex worker (FSW) interviewed by 9 male and 7 female interviewers
Including interviewer gender did not affect our associations of interest, over and above interviewer random effects. In this analysis of data from an Human Immunodeficiency virus (HIV) self-test trial among FSWs in three Zambian border towns, we show that interviewers often substantially affected what respondents reported regarding their lives, in particular their psychological wellbeing and experiences of violence
In a trial of HIV self-testing among FSWs in Zambian border towns, we found very high levels of interviewer-level variability in responses to sensitive questions
Summary
This may be due to random variation in interviewers’ ability to put respondents at ease or in how they frame questions. It may be due to systematic differences such as social distance between interviewer and respondent (e.g., by age, gender, ethnicity) or different perceptions of what interviewers consider socially desirable responses. Exploration of such variation is limited, especially in stigmatized populations. Social distance theory suggests that when interviewers and respondents are similar, response rates and item quality should be higher, due to respondents being more at ease and more likely to be honest [4]. Social role theory suggests that interviewer effects may be different for different types of question, with a strong effect when asking about topics linked to roles expected to be espoused by interviewers, e.g., reporting more caring behaviour to female interviewers, reporting less racism to ethnic minority interviewers [6]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
