The Science Behind Personality Tests

What they measure, how they work, and why they matter at work

Ever taken a ‘personality test’ to see which Harry Potter character you are?

Many of us are intrigued by the personalities of ourselves and those around us, however unsubstantiated ‘personality tests’ often blur the line between science and myth.

Our personality shapes how we think, behave, and interact with others every day, which means it inevitably shows up at work too. For this reason, assessing individuals’ personality at work can help them to develop in their roles, or help organisations make better-informed selection decisions.

To achieve these benefits, it is important to understand the science behind personality assessments and the principles that underpin their use in the workplace.

What ‘personality’ actually means in psychology

Many theories have attempted to explain personality, but there is a lack of agreement among the experts. A typical definition comes from Child (1973):

“The term ‘personality’ refers to more or less stable, internal factors that make one person’s behaviour consistent from one time to another, and different from the behaviour other people manifest in comparable situations”.

In other words, personality can be seen as the internal preferences that drive behaviours across different situations. For example, the ‘people person’ may prefer to socialise with others, and so they spend time meeting and talking to different people.

Theories of personality

There are two main approaches to understanding personality: type theory and trait theory.

Type theory assumes people can be categorised into different personality groups, depending on which is engaged with most frequently or dominantly. For example, type theorists would likely label the ‘people person’ as an extravert, instead of an introvert.

Whereas trait theory assumes that there is a common, underlying characteristic (or trait) that can explain the behaviours we see people showing. For example, trait theorists suggest that there is a continuum of behaviours between introversion and extraversion, and the ‘people person’ would likely be towards the extraversion end.

The relationship between personality traits and behaviour

Behaviour is what we can see, while personality traits are the internal explanations we use to understand that behaviour. It is important to recognise that although personality influences how we act, the relationship is not fixed.

People can learn to adapt their behaviour to fit a specific situation, like leading a conference presentation, without their underlying personality preference for extraversion changing at all. For example, the extraverted ‘people person’ will not always be highly sociable and expressive, but is also capable of working independently, which may just require more conscious effort than others.

Why personality is important in the workplace

In organisational settings, personality assessments, such as the HUCAMA Personality Factors, measure candidates’ typical behaviour and preferences in order to predict how they will perform in a role.

In recruitment, personality assessments can be used to compare a candidate's personality preferences to the specific requirements of a given role. This allows organisations to identify candidates’ strengths and potential concerns relative to the job's demands, ensuring a better fit for the role. Using personality assessments in such ways can enhance the overall accuracy of hiring decisions.

In development, personality assessments can be used to increase self-awareness and identify specific areas for professional growth. For example, the extraverted ‘people person’ may naturally prefer frequent collaboration and discussion, but could benefit from developing their confidence in self-directed or independent work when required. Managers can use these insights to inform training needs or tailor roles to individual strengths, helping to create more productive and satisfied teams.

To see how personality assessments look in action, you can download a sample HUCAMA Personality Factors, Personal Report, or read more about the HUCAMA Personality Factors on our website.

If you would like to learn more about using personality assessments effectively, our BPS Test User: Occupational, Ability & Personality course provides the skills and confidence needed to administer and interpret personality assessments with ease.

Do you have questions about getting started, or are you wondering how to use psychometrics effectively in your organisation? Please contact us.