Principles of Evidence-Based Interviewing
Familiar old ways of hiring are failing to meet the moment. It’s increasingly obvious that employers need a new approach that fairly assesses candidates during video interviews and more accurately determines who will be successful in a virtual work environment.Organizations want to build more diverse teams and want to reduce bias throughout the hiring process. By now we've all seen the research indicating that more diverse teams are smarter, more creative, and perform better financially. Employers are frustrated, recognizing that differential treatment by race (and other factors) is still commonplace in hiring. But even with bias prevention training and the best of intentions, outdated hiring practices often result in hiring people who are demographically similar to their hiring manager.
It’s time we broke that cycle of failure by interrupting the patterns of behavior that created it.
Better approaches to hiring already exist. The research that supports them is clear and compelling. Let's not blame the individual hiring manager when hiring problems are systemic. What’s needed is an evidence-based approach to hiring that directly addresses the mental errors and systemic bias inherent in common hiring practices.
The hiring process itself should be methodical, predictable, and data-driven. The process should diminish bias and elevate and emphasize factors that actually predict success on the job. The information from the hiring process should be methodically gathered, stored, analyzed, and used to continuously improve hiring results (similar to an agile methodology). At Staffing Advisors, we’ve supported our clients with Evidence-Based Interviewing for more than a decade, across more than 800 searches with over 100 different employers. We know from experience that this approach will be initially unfamiliar to most hiring managers, but nothing prevents any employer from using it. The key is simply getting started. Once managers can see for themselves how a better process improves diversity and reduces hiring mistakes, they will wonder why they didn’t try it sooner. And because video interviews scramble the hiring decision in new ways, managers are already being forced to adapt.
The time for change is upon us.
Emphasizing attributes is where hiring often goes wrong
When hiring managers are asked to describe their ideal candidate, they can usually list a series of abstract attributes they would like to see, such as strategic thinking, potential, and political savvy. This is a common component of job descriptions, and that's fine (as long as you provide some additional context).
The problem occurs during the interview, when various interviewers try to determine if a candidate possesses those desirable attributes. Usually, the interviewers have no trouble forming an opinion, although they often disagree with each other. (Following the interviews, they usually discuss who they “liked.”) And finally, in conducting reference checks on candidates, previous supervisors will also readily share their opinion about the candidate, usually using similar abstract attributes. Everyone involved in the hiring process is usually confident in their opinion … but decades of research shows that their confidence is misplaced.
Emphasizing the discussion of attributes is a root cause of error in the hiring process.
The problem with discussing attributes is that the hiring manager, the other interviewers, and the previous supervisor each have a different opinion about the meaning of those abstract attributes. In a recent post in Harvard Business Review, Marcus Buckingham and Ashley Goodall shared research showing that we humans are unreliable raters of other humans.
“Over the past 40 years psychometricians have shown in study after study that people don’t have the objectivity to hold in their heads a stable definition of an abstract quality, such as business acumen or assertiveness, and then accurately evaluate someone else on it. Our evaluations are deeply colored by our own understanding of what we’re rating others on, our own sense of what good looks like for a particular competency, our harshness or leniency as raters, and our own inherent and unconscious biases. This phenomenon is called the idiosyncratic rater effect, and it’s large (more than half of your rating of someone else reflects your characteristics, not hers) and resilient (no training can lessen it).” They conclude that “Deep down we don’t think we make very many errors at all. We think we’re reliable raters of others. We think we’re a source of truth. We aren’t. We’re a source of error.”
In the face of forty years of evidence, it’s time to rethink how we interview candidates. It’s time to retire the familiar but unproductive discussions of attributes and find better ways of determining whether someone can actually do the work.
More than 10 years ago, Stanford professor Bob Sutton examined the literature on methods of predicting job performance and concluded:
“…unstructured interviews, although of some value, are not an especially powerful method, despite their widespread use. Interviews are strange in that people have excessive confidence in them, especially in their own abilities to pick winners and losers -- when in fact the real explanation is that most of us have poor and extremely self-serving memories.”
Because this change in interview practices feels so unfamiliar -- such a departure from the conventional wisdom --I’ll share a third professorial view (including links to even more compelling evidence). Wharton professor Adam Grant recently wrote:
“In organizational psychology, we have over a century of evidence on why job interviews fail and how to fix them.”
He suggests there are three basic interview mistakes most employers make:
- “The first mistake is asking the wrong kinds of questions. Some questions are just too easy to fake. What’s your greatest weakness?”
- “The second error is focusing on the wrong criteria. At banks and law firms, managers often favor people who went to the same school or share their love of lacrosse. Across industries and occupations, economists find that even when candidates’ résumés are identical, those with white-sounding names like Allison and Matthew get 50 percent more callbacks than those with African-American-sounding names like Lakisha and Jamal.”
- The third error is overemphasizing the role of the interview itself. “Job interviews favor the candidates who are the best talkers.”
Methodically evaluating competencies is how hiring gets back on track
The researchers are all quite clear that the key to better hiring is reducing the discussion of attributes (and opinions) and replacing it with a methodical review of someone’s job competency—their ability to do the work.
Job competency or job knowledge is sometimes referred to as KSA (Knowledge, Skills, and Ability). Attributes (like hard-working) could apply to employees in any department, but job competencies tend to be focused in a specific functional area (the ability to do a cash flow projection, or design a benefits plan, or develop an integrated marketing campaign, or write a press release.) Competencies can be taught and tested, and different evaluators will tend to agree on whether someone can do that task in your work environment.
In the paragraphs below, I’ll share how the three researchers describe the process, but because researchers tend to use slightly different words to describe job competency, I have edited each quotation for clarity.
Professor Grant noted, “We can overcome some of these biases with structured interviews: identifying the key skills and values [competencies] in advance, and then creating a standard set of behavioral and situational questions to ask every candidate.” He concludes that this approach can “double or even triple” your ability to predict job performance.
Almost a decade ago, in his best-selling book, Nobel Prize winning Princeton professor Daniel Kahneman suggested a similar way to reduce bias in hiring:
“If you are serious about hiring the best possible person for the job, this is what you should do. First, select a few traits [competencies] that are prerequisites for success in this position – six dimensions is a good number. The traits [competencies] you choose should be as independent as possible from each other, and you should feel that you can assess them reliably by asking a few factual questions. Next, make a list of those questions for each trait [competency] and think about how you will score it, say on a 1–5 scale. You should have an idea of what you will call “very weak” or “very strong.” These preparations should take you half an hour or so, a small investment that can make a significant difference in the quality of the people you hire. To avoid halo effects, you must collect the information on one trait [competency] at a time, scoring each before you move on to the next one. Do not skip around. To evaluate each candidate, add up the six scores.”
After reviewing the research, Professor Sutton recommended the following:
“The upshot of this research is that work sample tests (e.g., seeing if people can actually do key elements of a job -- if a secretary can type or a programmer can write code), general mental ability (IQ and related tests), and structured interviews had the highest validity of all methods examined … the most powerful predictors of job performance were GMA [general mental ability] plus a work sample test (in other words, hiring someone smart and seeing if they could do the work), GMA plus an integrity test, and GMA plus a structured interview (but note that unstructured interviews, the way they are usually done, are weaker).” Professor Sutton did acknowledge that “…there is a lot of controversy about IQ, with many researchers now arguing that it is more malleable than previously thought.”
Beware of opinions masquerading as facts
A rigorous evaluation of job competencies will also reveal quite a bit about cultural fit – how the candidate’s values and work preferences might fit in with your organization’s work style. We recommend that you develop a set of questions you will ask each candidates, and then develop a second set of questions for you to reflect on after the interview. Here's an example, using HR strategic thinking as one of the job competencies:
I recommend that you be very careful when you are gathering feedback from other interviewers. To avoid group think, It's best to gather feedback privately, rather than in a group setting. Be sure to ask each interviewer specific questions about job competencies first, and gather their thoughts about strategic fit by asking specific questions. Keep your focus on gathering facts, and try to avoid any discussion of who anyone “likes.” This is exceedingly difficult to do. You will find that other interviewers are far more willing to share opinions, but if your goal is to improve your hiring results, it’s important to keep the conversation focused on evidence. (For examples of how to approach this, see How to Avoid Groupthink in Hiring and also How to Assess Cultural Fit Without Perpetuating Bias).In hiring discussions, opinions abound and facts are scarce. It is quite common for people to present their own personal opinion as if it were a fact about one of the candidates. Be sure you ask the right questions to get at the facts. When someone has presented an opinion, such as, “The people who work at that organization are all bureaucrats,” consider asking them “How would we learn if that’s true for this candidate?” Or “How can we better understand how that might relate to their performance in this role?”
The core practices of Evidence-Based Interviewing include:
- Before the interview, define the key competencies (not attributes) that will drive results.
- Use a structured process to consistently evaluate the competencies in the interview.
- Do some work together in the interview (see our advice on work sample testing here).
- Structure the interview debriefing to focus on facts.
- Verify accomplishments during evidence-based reference checks.
- Track your results and use the data to improve.
- The best predictor of doing work on the job is doing work together in the interview.
- The best interview questions are questions about work and follow-up questions that delve into how the work was getting done.
- The best interview evaluation criteria are competency-based, not opinion-based.
- The best hiring decisions are made when you establish your interview structure, criteria, and participants in advance.
- Stick to the facts and avoid discussion of opinions.
- The Case for Evidence-Based Interviewing
- Avoiding Groupthink in the Hiring Process
- How to Handle Panel Interviews
- How to Evaluate a Video Interview
- How to Assess Cultural Fit Without Perpetuating Bias
- How to Select Resumes Without Perpetuating Bias