Interview questions are far more than a formality—they are a strategic tool for uncovering the true potential of candidates. In Industrial/Organisational (I/O) psychology, the process of designing interview questions begins with a deep understanding of the role and the competencies required for success. 

To design effective interview questions, we start by understanding the job and what makes someone excel in it. This means figuring out the key skills and qualities (like teamwork or problem-solving) that lead to success.

Typically, we use a structured behavioural-based interview—where every candidate gets the same questions. Interview questions focus on the key competencies required to perform successfully in the role and ask candidates to share real examples from their past to see how they’ve demonstrated the competencies or skills you’re looking for.

Why? A structured behavioural interview will:

• Predict who will do well in the job.
• Help you avoid costly hiring mistakes.
• Make the process fairer for everyone.
• Guide not just hiring, but also any training or development needs.

Of course, behavioural interview questions are not the only questions you will want to ask. It's a great idea to start off your interview by asking the candidate why they're interested in the role and what motivated them to apply for it. This helps give you a sense of their commitment and interest in the role and in working for your organisation.

So where do you start?

First – understand the role you are recruiting. This means you need to identify the main tasks responsibilities and challenges of the position. A good place to start is to ask the person who's actually doing the job.  You will also use the position or job description as this is always the foundation document of your recruitment approach.  Your position description should set out what the key tasks of the role are, and the core competencies, skills and abilities that a successful candidate will need to demonstrate.  Having a chat to the incumbent and reviewing the position description, will ensure that you have an up-to-date position description to recruit to.

Utilising the core competencies of your job, you can utilise AI to generate questions - the proviso here is that you check the question aligns with what the competency definition is.  For example, here are two structured behavioural interview questions generated by AI, that assess – or measure -  Problem Solving:

1. “Tell me about a time when you identified a problem that others hadn’t noticed yet. What was the problem, and how did you address it?”
   • This question assesses your ability to recognize issues early, analyze their impact, communicate with stakeholders, and take initiative to resolve them.
2. “Describe a situation where you had to solve a problem with incomplete information. How did you approach this challenge?”
   • This question evaluates your approach to uncertainty, resourcefulness in gathering information, risk assessment, and decision-making under pressure.

How many questions do you need? 

This is guided by the level of position that you are recruiting for, i.e. an administrative-type role would typically have around 4 behavioural questions along with the 'why are you interested' in the role question.  A management leadership or executive position would typically have 5 to 7 questions in addition to the 'why are you interested'  (or some variation of that) question, in the role.

Another thing to think of when assessing candidates,  is the fact that a work test or a work sample (based on a key activity the person would be expected to perform in the role) is actually more predictive of performance at work.  Rather than relying on interview questions alone, you can have also have a work test i.e. you may ask candidates to prepare a presentation on a subject related to the job. We'll talk in more detail about work tests in a future post – or see our recruitment page where we've provided a guide on work tests.

The next step we recommend is to test your questions, you can do this in two ways:

1. Read the questions out loud to yourself. How do ‘feel’ when you read them?  Are they too long and wordy? The written word is different to the spoken word, so are you comfortable with the language and what the question is asking?
2. Test them on someone. It’s a good idea to ensure that this person is a trusted helper and won’t give questions to the actual candidates! Ask your ‘test’ person what they think of the questions, and again check for fluency, do they make sense? Is the language consistent with your organisation and culture? Did your 'tester' understand them?

Once you've reviewed your questions and are comfortable with them, the next and perhaps most important part, is creating a rating scale on how you are going to score candidates' answers. This is the part where you're going to measure the level of competency that a candidate has demonstrated in responding to your question. Typically, we use a 1-5 scale where a ‘5’ is a very strong demonstration of the competency and ‘1’ represents poor demonstration of the competency.  It is this scoring system that will help identify the best candidate for the role.  It is also important to ensure that you are assessing candidates fairly, so ‘anchoring’ your scale is a must. This simply means you subscribe a rating or evaluative word to each number. For example, 1 = poor, 2 = limited, 3 = acceptable, 4 = strong and 5 very strong.  It’s helpful to put some additional context around your scale too – such as 5 = very strong ‘demonstration or evidence’ of the competency etc. This helps your interview panel align on assessing candidates in a reliable and consistent manner and agree on what a ‘5’ looks like.

Important point on your interview panel...

Rater reliability - or how aligned your panel raters are - is key to an effective selection system.  This means that your competencies are well defined, your raters are familiar with the competencies and questions - and the key skills and experience a candidate will require to perform successfully in the role.  The other consideration is that all of your panel understand the rating score - so what does a '5' look like in terms of what you'd expect a candidate to say.  The same goes for the rest of the scores 1 through 4 - your panel need to have an understanding of what those numbers represent.

Why it matters…

Creating interview questions through the lens of Industrial/Organisational psychology is a rigorous, science and evidence-based approach. By anchoring questions in validated competencies and utilising an anchored behavioural rating scale that your panel understands and is familiar with - organisations can make smarter hiring decisions, build stronger teams, and drive high performance. Last but not least – a structured interview process ensures you’re hiring the best person for the job, first time. Measuring competency in a standard, reliable and valid way, isn’t just a hiring best practice—it’s a strategic imperative for long-term success.

Selectio partners with organisations to design interview formats that are both reliable and valid, ensuring your questions truly measure the competencies that matter most. By leveraging evidence-based methods and deep expertise in Industrial/Organisational psychology, Selectio helps you build structured interviews that lead to smarter hiring, stronger teams, and lasting business success.  We’re here to help you and can provide recruitment support tailored to your needs – as little – or as much – as you require.