3 May 2021

3 types of hiring bias causing unfair screening and how to eliminate them


Biased recruitment. When we are talking about this subject, we tend to focus most on bias arising from a candidate’s demographics – age, gender, race, etc. However, hiring bias is about much more than that, of which we are most likely not even aware. And although there are lots of different biases, focusing on lots of different candidate aspects, the consequence is the same for all: A talent pool that is decreased in terms of both size and diversity.

In this blog, I will dive into the 3 most painful types of hiring biases that negatively impact our screening efforts, and how to prevent those biases from happening – both during the screening process, as well as your interviews.


Bias 1: Affinity/similarity bias

Affinity/similarity bias happens when we favor a candidate because we share a characteristic with them – for example, we went to the same university or worked at similar companies. This one is especially tricky from a cultural perspective

From a culture fit perspective, we want to hire ‘like-minded people’ – people who have the soft skills that represent our core values. And there’s not necessarily something wrong with that. However, as soft skills are hard to assess from a resume, we tend to focus on secondary information (resume information) and make an assumption about someone’s soft skills based on this information. This can lead to either wrongfully rejecting candidates who actually have the soft skills we’re looking for, or advancing candidates who don’t have the soft skills we’re looking for.

During a job interview, this is often perpetrated by asking candidates about their personal life, hobbies, and other non-job-related questions. Just because we assume that someone with the same hobbies will also have the same soft skills as we have ourselves.


How to prevent affinity/similarity bias

This type of bias can be prevented in two different ways. There’s an option that’s not free, which is more accurate, as well as an option that’s free. And although the free one is not entirely objective, it’s at least a step in the right direction. 

Free option to prevent this bias: Open questions

Include some open questions in your job application to get to know the candidate better, and try to focus on these questions first, before diving into the resume information.

For example, ask why they want to work at your company, what they would like to achieve in life, what their biggest achievement has been so far, or why your company’s vision and mission stood out to them. But also include more situational questions that allow you to gain more insights into their way of thinking for example.

Non-free option to prevent this bias: (Soft) skill assessment

Assess soft skills right away, by making use of assessment tooling, so that you’re not required to make assumptions.

Here at Equalture, we build hiring software that lets candidates complete a set of neuroscientific games during their initial job application. This ensures that once a candidate has completed their application, you instantly have an objective, data-backed insight into their skills, talents, and personality. 

(soft) skill assessment that helps to prevent bias

When candidates apply at one of our own jobs at Equalture, they will be asked to complete a set of games right away.


Bias 2: Contrast Effect

The Contrast Effect happens when we compare two or more candidates. When you have seen a very impressive profile, which might be way better than the job requires, you unconsciously will raise the bar for the next profile you’re looking at. The same thing also happens the other way around – when reviewing a profile that you don’t like first, you tend to be satisfied more easily with the next profile. This effect causes an extreme level of subjectivity in your screening process, which can seriously damage your talent pool.


How to prevent the Contrast Effect

You can only prevent the Contrast Effect by implementing methods to ensure objectivity, or at least standardised screening methods. 

Free option to prevent Contrast Effect: Screening checklist (Yes/No)

Create a screening checklist for yourself, in which you include the candidate characteristics that are crucial to you. Only work with yes/no questions, so that you force yourself to focus on a minimum/bar, rather than a range. You can then decide to continue with all candidates with at least 75% ‘yes answers’. 

Also, when extracting this to the interview stage, what prevents your interviews from suffering from the Contrast Effect, is having structured interviews and score cards in place. Make sure to ask all candidates the same set of questions, and rank them on these questions. This again takes the subjectivity largely out of it and allows you to focus on who scored most points for example.

Non-free option to prevent Contrast Effect: Benchmarking

As I already explained in the affinity/similarity bias section, measuring skills directly is for sure the most objective way to get to know your candidates – however, that also requires an investment.

What many assessment tools do have though, is the option to benchmark candidates against another data source. By doing so, you can set rules for yourself (for example, the candidate should meet benchmark x) and stick to those rules when evaluating candidates.

Our software, as mentioned before, makes use of neuroscientific games – validated assessments, measuring skills and behaviours, designed in a gaming setting. What is without a doubt our favourite feature (however, as I proposed it out myself, I might be biased ;-)), is our Teams feature. This feature allows you to let your current team complete the games also, to create an internal benchmark. 

This internal benchmark provides you with two data points:

  • Your team average score on a certain skill/behaviour;
  • The average score of similar teams on this certain skill/behaviour. 

By having this, you can easily benchmark your candidate against these data points, which prevents you from suffering from the Contrast Effect.

Screenshot of the benchmarked score of a candidate that applied with Equalture's neuro assessment games

Equalture’s Candidate Profile: A candidate’s score on a game is benchmarked against the current team, the industry, and other candidates.


Bias 3: Halo & Horns Effect

Finally, we have the Halo & Horns Effect. The Halo Effect and the Horns Effect are the exact opposites of each other, so let’s explain them one by one:

  • Halo Effect: One positive thing about someone makes you wrongfully look more positively at all other aspects also;
  • Horns Effect: One perceived bad quality makes everything about this person seem less positive. 

During a screening process, this can easily lead to wrongfully rejecting high-potential candidates. During an interview process, you might get so blinded by this one positive thing, that you end up making a mishire.


How to prevent the Halo & Horns Effect

When looking for a free option, you can apply the same solution like the one proposed for the Contrast Effect. This forces you to always look at all different aspects of a candidate, both during screening and the interview.

When looking at the non-free option, you can apply the same solution as the one proposed for the affinity/similarity bias. When having a complete assessment of a candidate’s skills, talents and behaviours, presented in one overview, you are more stimulated to not only focus on the cons, but also on the pros.



So, as there’s always a method to eliminate hiring bias that doesn’t require an investment, there’s no longer an excuse to not worry about and act on this issue. And in case you’re curious to learn more about how our gamified approach might help, you know where to find us.

Charlotte Melkert Co-Founder and CEO of Equalture in Portrait picture

Cheers, Charlotte
Founder & CEO