Hiring Interview Effectiveness Research
Interviews Are An Important Part Of The Hiring Process
But Research Shows That They Are Subject To Unconscious Interviewer Bias

How Effective Are Interviews?
Research shows that structured interviews typically have a .14 correlation with hiring top performing employees.
One of the reasons for this is that structured interviews are influenced by the natural biases of even the most experienced interviewers. This can happen as soon as within the first twenty seconds of the interview.
To help you explore theimpact that this might be having on your hiring decisions, here are three research studies that examine the impact of unconscious interviewer bias in the hiring process.
One of the ways to counter this bias is to use validated hiring assessments to supplement the information obtained during the interview.
The Impact of Interviewer Bias on Hiring Decisions
Without a doubt, most hiring managers and HR professionals who are interviewing job candidates for a position do their best to be objective and pick the best candidate for the job.
Unfortunately, human nature can get in the way of being as objective as needed during the interview.
In these three major university research studies, researchers investigate the impact of unconscious bias on the final outcome of the interview. You can review the overview of the results or each report and download the complete reports below.
Here are the major conclusions of the three studies:
- Interviewers can form an initial opinion of the candidate within as little as twenty seconds and this opinion influences the way the rest of the interview is conducted.
- Candidates with high extraversion and verbal skills are evaluated more favorably than those who are more introverted.

Initial Evaluations in the Interview
Relationships with Subsequent Interviewer Evaluations and Employment Offers
The authors of this study examine how evaluations made during an early stage of the structured interview (rapport building) influence end of interview scores, subsequent follow-up employment interviews, and actual internship job offers. Candidates making better initial impressions received more internship offers and higher interviewer ratings.
As predicted, initial evaluations of candidate competence extend beyond liking and similarity to influence subsequent interview outcomes from the same interviewer, from a separate interviewer, and from another interviewer who skipped rapport building. In contrast, assessments of candidate liking and similarity were not significantly related to other judgments when ratings were provided by different interviewers.
The findings of this study thus indicate that initial impressions of candidates influence employment outcomes, and that they may be based on useful judgments of candidate competence that occur in the opening minutes of the structured interview.

The Importance of First Impressions in a Job Interview
In the this study, naive observers evaluated the initial greeting that took place within 59 employment interviews.
Two trained interviewers conducted each employment interview, which was videotaped. After each twenty-minute interview, the two interviewers completed a post-interview questionnaire evaluating the candidates on their interview performance, behavior, rapport, and professional skills. These evaluations constituted the interview outcome criteria that we attempted to predict. Brief video clips were extracted from the recordings such that each began when the interviewee knocked on the door and ended five seconds after the interviewee sat down. Only the interviewee could be seen on the video. The video clips were shown to naïve observers who rated the interviewees on 12 interpersonal attributes, among these were hirable, competence, and warmth. These judgements were used to predict the outcome of the interview, operationalized as the mean of the two interviewers’ assessments.
Naïve observer judgments based on the initial 20-seconds significantly predicted interviewers’ assessments who questioned the applicants for over 20 minutes. The present study showed that a personnel director’s assessment of an applicant’s skill, knowledge and ability might be fixed as early as the initial greeting of the formal interview.

Candidate Characteristics Driving Initial Impressions During Rapport Building:
Implications for employment interview validity
We examine the antecedents impacting interviewers’ initial impressions of candidates formed during the rapport-building stage of the interview and subsequent evaluations of answers to highly structured interview questions.
Ratings for 130 mock interview candidates reveal a strong relationship between interviewers’ initial impression of the candidate and their evaluations of candidate responses to structured questions. These initial impressions correspond with candidate extraversion and verbal skill, controlling for job qualifications. Interviewers’ initial impressions mediate the effect of candidate characteristics, relevant for some jobs more so than others, on later evaluations.
Thus, initial impressions formed during rapport building appear to influence subsequent evaluations whether they are clearly job-relevant or not. These findings have important implications for the validity of structured interviews.
Use Multiple Interviewers
Always have at least two different people ask the same questions and record their answers. Then have either neutral third party compare the results or have the two interviewers discuss their observations and come to agreement.
Don’t Let Managers Hire Their Own Direct Reports
This eliminates the “I like them because they are like me” unconscious bias that is part of human nature. Someone who doesn’t have a personal interest in the outcome of the hiring decision will be less influenced by this natural tendency.
Add A Hiring Assessment To Your Process
A well designed and validated hiring assessment can add valuable objective information to the hiring process. We will be glad to talk discuss your hiring process and give you our best recommendation for your particular situation.