When interviewing as part of the hiring process, there are ways in which to make them more effective. It is important to note, however, that interview data used on their own can be problematic (see our article Optimise your hiring process) but, in conjunction with other data, they can add value.

Broadly speaking, there are two types of interviews, unstructured and structured.

Unstructured interviews follow no predefined procedure. They can consist of any question the interviewer feels like asking in the moment, which may or may not be related to the role and is likely to differ between candidates.

Structured interviews, of which a “competency-based interview” is one, allows an interviewer to ask many different candidates the same question, which allows for easier comparison of data. The questions are also strictly based on role requirements – they do not pertain to any personal questions or questions that are perceived as irrelevant.

Although both styles have their pros and cons – many countries, including South Africa, are governed by labour laws. In South Africa, the main purpose of the Employment Equity Act, No. 55 of 1998 (EEA) is to promote equal opportunity and fair treatment in employment through the elimination of unfair discrimination. The EEA is clear that an employee must only disclose that information during an interview that is part of the inherent requirements of the job. One way of ensuring fairness is the use of structured competency-based interviews.

It has been suggested that interviews can add something not covered in an assessment. This is true as it explores job-specific activities and scenarios, whereas assessments are more holistic. Research shows that interview questions that are based on specific job competencies – identified through job analysis as being critical to job success – demonstrate high levels of legitimacy and reliability, and decreased levels of adverse impact.

Incremental validity refers to the extent to which a new assessment adds to the prediction of job success above and beyond the predictive powers of an existing assessment. Research has shown that, used alongside cognitive and personality psychometric data, structured interviews add an increment of 18% more predictability.

If used as part of the hiring process, where psychometric assessments are used first (see our article Optimise your hiring process), structured interviews can provide useful additional information.


Bohnet, I. (2016). How to Take the Bias Out of Interviews. Harvard Business Review. Retrieved from https://hbr.org/2016/04/how-to-take-the-bias-out-of-interviews

McFarland, L.A., Ryan, A.M., Sacco, J.M. & Kriska, S.D. (2004). Examination of Structured Interview Ratings Across Time: The Effects of Applicant Race, Rater Race, and Panel Composition. Journal of Management, 30(4), 435-452.

McLeod, S.A. (2014). The Interview Method. SimplyPsychology. Retrieved from https://www.simplypsychology.org/interviews.html

Parkinson, M. (2015). Are Psychometric Tests ‘Better’ Than Interviews? LinkedIn. Retrieved from https://www.linkedin.com/pulse/psychometric-tests-better-than-interviews-dr-mark-parkinson/

Rheeder, J. (2018). Legal Aspects in Recruitment and Selection. Johanette Rheeder Incorporated. Retrieved from https://www.jrattorneys.co.za/south-african-labour-law-articles/employment-equity-and-unfair-discrimination/legal-aspects-in-recruitment-and-selection.html

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