How to Eliminate Interviewer Bias
by Mike Poirier
Summary: Regardless of the type of interview, the interviewer can, wittingly or unwittingly, create a situation in which the respondent replies in a manner that reflects what he or she believes the interviewer wants to hear. Objective interviewing requires both the interviewer and the respondent to say precisely what they mean and mean precisely what they say.
Recently I got a taste of the data collection process by lending a hand training Brand Ambassadors in best practices for conducting surveys at sampling events. There are some basic guidelines that cannot be ignored in the interviewing process, especially when you’re administering a multitude of surveys in a short period of time.
A major difference between conducting surveys in the field, rather than on the web, is that the questions asked in the field are read aloud to the respondent instead of the respondent viewing the questions on a screen. That may not sound significant, but if an interviewer doesn’t read the question the same way to every respondent (i.e., without changing any words), the survey results may be skewed, because there is no way to tell if the data collected accurately reflects the exact question as developed for the survey. We call this “Interviewer Bias.”
To prevent Interviewer Bias, we provide three simple instructions for interviewers when conducting surveys:
- Read each question exactly as it appears.
- Don’t interpret the question for the interviewee.
- Offer to repeat the question exactly as it appears.
We instruct our interviewers to ask the respondents to answer based on their best understanding of the question, if they say that they are unsure of what the question means. Any addition, subtraction, modification, interpretation, suggestion or change in vocal inflection by the interviewer has the potential to stimulate a biased response.
We want our interviewers to be as objective as possible.
Even though there is no guarantee that every question will be interpreted the same way by all respondents, it does ensure that they’re all responding to the same, exact question. This is an important step toward ensuring clean, accurate survey data.
Photo Source: http://www.flickr.com/photos/zoethustra/520668071/