Structured interviews are the highest-leverage DEI intervention
Nothing else in the hiring toolkit has as much peer-reviewed evidence for reducing bias and improving predictive validity.
DEI programmes have proliferated in the last decade, with mixed and sometimes disappointing results. Unconscious bias training, in particular, has a growing body of evidence showing minimal or short-lived behavioural change. Meanwhile, one of the oldest and best-supported interventions in the hiring literature continues to be overlooked: the structured interview.
A structured interview uses the same predefined questions, evaluated against the same rubric, for every candidate for a given role. The format sounds mundane. Its effects are anything but. Meta-analyses spanning more than eighty years of research find that structured interviews are roughly twice as predictive of job performance as unstructured ones. Just as importantly, they substantially reduce demographic bias in ratings because the evaluator has less room to substitute impressions for evidence.
The mechanism is well understood. Unstructured interviews reward interviewer confidence in judgement, which is systematically higher than justified. Structured formats force the evaluator to compare candidates on the same evidence and to record a rating before discussion, which limits anchoring and groupthink. When paired with diverse hiring panels and calibration sessions, the effect on both quality of hire and representation compounds.
For HR the implementation is unglamorous but effective. Define the four to six competencies that actually predict success in the role. Write behavioural questions for each, with anchored rating scales. Train interviewers on the rubric, not on abstract bias concepts. Require independent scoring before the debrief. None of this is expensive. All of it is measurable. And unlike most DEI initiatives, it has decades of peer-reviewed evidence behind it — evidence that HR teams can quote with confidence to the executives who will ask why it matters.
Structure begins before the first candidate arrives. The hiring team must agree which competencies are essential, what evidence would demonstrate each one and which questions will elicit comparable examples. Questions should be relevant to the role and reviewed for unnecessary barriers. Anchored scales describe weak, acceptable and strong evidence in behavioural terms. This preparation reduces the temptation to redefine success after meeting a candidate who feels familiar or particularly charismatic.
During interviews, consistency matters without requiring a robotic conversation. Interviewers can ask planned follow-up questions to clarify an example, provided each candidate has an equivalent opportunity. Notes should capture evidence rather than impressions, and ratings should be completed independently before the panel discussion. Candidate experience also improves when the process is clear: people know what will be assessed and are less dependent on decoding an interviewer's preferred conversational style.
HR should audit the process from application to offer. Compare progression rates, score distributions and disagreement between interviewers, while protecting privacy and avoiding conclusions from very small samples. If one question produces little differentiation or adverse patterns, review its relevance and wording. Structured interviews are not a complete diversity strategy; sourcing, accessibility, job design and promotion still matter. They are, however, a controllable point where evidence can replace intuition and where selection decisions can become more consistent, explainable and job-related.
Candidate communication is part of the structure too. Give applicants a reasonable description of the format, offer adjustments and explain the next steps. Consistency does not require withholding useful information. In fact, reducing avoidable uncertainty allows candidates to spend more attention demonstrating relevant capability. After the process, retain only necessary notes according to applicable privacy rules. A disciplined record supports review and accountability without becoming an unnecessary collection of personal information.