Nutshell: Beyond the fortune cookie – navigating the tricky world of personality testing

Properly used, the right personality test can provide relevant insights into our own default traits and how these can support or undermine our leadership.

Go on, be honest. Most of us at some time will have whiled away a happy five or so minutes on a BuzzFeed quiz that tells us which autumn colour we are (pumpkin orange?) or how we can reveal which type of sandwich matches our personality in 10 simple questions. 

We may know, deep down, that it’s all a load of nonsense, but the drive to find out something about ourselves, especially if it ends up reinforcing what we like to think about our personal qualities, is compelling. Why else would these themed personality quizzes remain such a staple of our popular culture? 

The answer, it seems, has a long history, and an application far beyond the harmless world of BuzzFeed. As part of a wider suite of psychometric testing tools, personality testing has become a staple of working life, an attempt to provide some much-needed data – or at least, an underpinning – when it comes to the messy, human business of how people behave and interact at work.

Whether it’s used for recruitment, personal development or teambuilding, that urge to find out more about, even categorise, ourselves and others means that testing looks like it’s here to stay.
 

Four humours and a Swiss psychiatrist

The American Psychological Association defines personality as “individual differences in characteristic patterns of thinking, feeling and behaving”. A personality trait is assumed to be a characteristic that’s relatively constant, as opposed to our more changeable behaviours. 

With flatter organisational structures and the move towards knowledge-based work, it’s little wonder that the urge to understand more about personality, what makes us tick, whether we’re more or less dependable, trustworthy or cheerful, has become so seductive. After all, it might provide useful clues to how we might respond or act in given situations, becoming an invaluable predictor for ourselves and others. 

It’s often said that modern psychometrics began with The Woodworth Personal Data Sheet (WPDS), a questionnaire developed by Robert S Woodworth during World War I to identify army recruits at greater risk for shell shock, and later adapted for use outside the military. But when it comes to personality testing and traits, we’re once again in the hands of the ancients. 

With more than a passing nod to the work of his predecessor, Hippocrates, the Greek physician, Galen, used his second-century BC treatise, Die Temperamentis, to speculate on physiological reasons for different behaviours in humans. Galen’s four temperaments, or humours, may eventually have been superseded as the basis of medical theory. But even the scientific revolution could not entirely discredit thinking about how the yin and yang of our personalities were informed by Galen’s typology of temperaments.

We might be sanguine (optimistic/volatile); choleric (driven/bad-tempered); melancholic (thoughtful/depressive); phlegmatic (content/resistant to change) – or a blend of more than one. 

If this all sounds familiar, that’s because it is. Galen’s theory of humours has been developed, adapted and reconstituted alongside the development of modern psychology, but the idea of default traits and preferences remains the foundation of the plethora of personality typologies and tests designed to support personal development and workplace relationships today.

Take, for example, the four-colour Insights Discovery model developed by The Colour Works, which provides individual and team personality evaluations based on whether we’re more or less red (choleric), green (phlegmatic), yellow (sanguine) or blue (melancholic). 

And then there’s the personality test to end all personality tests, the Myers-Briggs Type Indicator (MBTI), credited with assessing and categorising more than 50 million of us since it was developed by Katharine Cook Briggs and her daughter Isabel Briggs Myers back in the 1940s and 1950s. 

MBTI is based on the work of Swiss psychiatrist Carl Jung, who posited that people experience the world using four principal psychological functions – sensation, intuition, feeling and thinking – and that one of these four functions is dominant for a person most of the time. In the hands of the Myers-Briggs duo, these became the four paired categories of Introversion/Extraversion, Sensing/Intuition, Thinking/Feeling and Judging/Perceiving.

By taking the test, we identify a preferred quality from each pairing, allocating us to one of 16 unique types, such as INTJ or ESFP, and offering a means of categorising personality traits in a way Galen might have understood. 

Myers-Briggs as fortune cookie?

We’ve already established that we all love a quiz, which perhaps helps to explain why MBTI is so perennially popular. Finding out which Harry Potter character shares your MBTI preferences is fun, right? And a bit of self-validation might be harmless enough. 

But MBTI – and other similar typing tools such as Enneagrams – also have a much more serious side. The Myers-Briggs Foundation website makes a bold claim that “much seemingly random variation in behaviour is actually quite orderly and consistent”, suggesting, perhaps, that our preferences can be marshalled and packaged rather more neatly than is really the case. 

That may not matter if we’re using MBTI as just one tool to aid self-awareness, or to help build a picture of those areas we need to develop to become a more rounded person. But it can be a blunt instrument if used in isolation, or, more widely, as the basis for recruitment, work allocation or promotions.

Once we’re labelled as an INTJ, that classification, in the wrong hands, can become a limiter rather than an enabler. It’s a danger neatly encapsulated by psychologist Brian Little, who observed that “insight from the Myers-Briggs can start that conversation, but unfortunately it often ends the conversation. You’ve got your type stamped on your forehead.”

In reality, our personality preferences are rarely at one extreme of a pair of opposites but somewhere along a spectrum. Even Jung himself acknowledged the limitations of this kind of typing. “There is no such thing as a pure extrovert or a pure introvert,” he wrote. “Such a man would be in the lunatic asylum.” We’re much more likely to be, say, 60% or 65% extrovert most of the time than 100% extrovert all of the time. 

There are also issues around the crucial scientific standards of reliability and validity. Retest reliability, for example, means that, if the same person takes the same test more than once, they should get more or less the same result. MBTI might find it difficult to make that claim. 

Research has reported that, across a five-week retest period, 50% of the participants received a different classification on one or more of the MBTI scales. 

It tends to suggest that the test might be measuring preferences that can quite easily be swayed by how we’re feeling or the situation in which we find ourselves. Psychologist Adam Grant uses his own variable MBTI results as a starting point for an eloquent critique of the test, marking it against four core social science standards – reliability, validity, independence and comprehensiveness – with a less than promising “not very, no, no, and not really”. 

MBTI’s terminology has also come in for criticism for being too vague and unspecific.

Commentators and thinkers have even bundled it in with astrology and fortune telling in terms of the Barnum effect, a bias tested and validated by psychologist Bertram R Forer in the 1940s. The bias feeds on our natural tendency to attach personal meaning to general statements, and is related to subjective validation, where a person considers information correct if it has personal significance. It means that we have a tendency to take a vague statement (especially a positive one) and find meaning specific to ourselves within it by connecting two things that might be entirely separate. 

Psychometric specialist Robert Hogan has even gone on record as saying that most personality psychologists regard MBTI as “little more than an elaborate Chinese fortune cookie”.

That doesn’t sound too promising for self-awareness. And, at an organisational level, there’s a real danger that data acquired in this manner might be misinterpreted in ways that reinforce prevailing narratives or oversimplify, rather than bringing a sense of objectivity to people management. 

Much, of course, depends on purpose – what the tests are used for and how. So, while they can be useful in providing a common language for conversations about personal preferences, development and difference, we need to guard against their use as what journalist Emma Goldberg calls “HR tailormade for the BuzzFeed quiz generation”. They can certainly inform decision making, but that doesn’t mean that they can make that decision for us. 

Sparking insights is one thing. Relying on Myers-Briggs and similar personality typing methodologies for anything more serious at work – and certainly in isolation – is quite another. 

Help is at hand: the Big Five (and Six)

So, if the likes of MBTI don’t quite stand up to the rigours of scientific reliability or validation, does that mean that any personality testing is fundamentally flawed? 

The answer is: not necessarily. Fortunately, not all tests are created equal. Using the right test at the right time in the right, finessed way, can bring benefits to individuals, as well as providing bias-busting objectivity for hiring and promoting. Like all tools, psychometric tests are only as good as the people who develop and use them. We need to keep that purpose at the fore, rather than being driven by what the test can do. And we need to choose the right test for the job. 

When it comes to personality, there’s widespread agreement among psychologists that the most reliable and valid tests are based on the so-called Big Five (or Five Factor) personality theory that, through years of rigorous and evidence-based research, has concluded that personality can be boiled down to five core factors, often summarised by the acronyms OCEAN or CANOE. 

Unlike black or white, on-off approaches to traits, each of the Big Five traits encompasses a range of other facets, which allows for a richer and much more diverse picture of our personalities.

For example, a scale that measures extroversion at the facet level might give a score on a range of traits such as sociability, assertiveness, activity, cheerfulness and excitement-seeking. Traits are also measured as a spectrum on a continuum from low to high, recognising that most people will fall somewhere along that spectrum rather than at one end or the other; as we’ve seen, a core criticism of Myers-Briggs. 

None of the five traits is, in itself, positive or negative; they are simply characteristics that we exhibit to a greater or lesser extent. Because the traits are measured independently of one another, our score on one trait does not influence our scores on other traits. So being reserved (low extraversion) does not necessarily mean that we must also be self-conscious (low emotional stability). We may be, but the Big Five allows for this more nuanced result. 

In terms of retest reliability, people score similarly throughout their lives, although research has found that, overall, we tend to score higher for agreeableness and conscientiousness as we age. There is also a closer correlation (better validity) between test results and how we actually behave, those all-important outcomes. 

Studies have shown that, perhaps unsurprisingly, conscientiousness is the strongest predictor of all five traits for job performance. Agreeableness can be an advantage for team working, but can be less positive when it comes to being proactive. Conversely, being open to new experiences is good for proactivity, but less of a positive for team working. 

HEXACO: Five becomes Six

Of course, the science behind the Big Five has not stood still. Researchers have questioned whether it is properly applicable across all cultures, and whether the trait descriptors are still too broad. There is also an argument from psychologists that we might need more than five traits to give a properly rounded view of personality. 

A new model, HEXACO, was developed by Kibeom Lee and Michael C Ashton in their book, The H Factor of Personality, following research into the validity of the Big Five across different languages and cultures.

The model retains the original traits from the Big Five Model, with Neuroticism renamed as Emotionality and slightly different interpretations of Agreeableness and Emotionality. It also adds one more, Honesty-Humility, which they describe as the extent to which one places others’ interests above their own. 

And it seems that the addition of this extra factor has been a positive, increasing the predictive power of assessments for important work outcomes, with the H Factor positively predicting positive workplace behaviours such as performance, adaptability and creativity – as well as less desirable characteristics like aggression or a predisposition for theft. 

Trait-based tools that use the HEXACO model – such as the Sova/Future Talent Learning Personality Assessment – also score us not just against own self-identified preferences (as MBTI does), but also against a ‘norm group’ of other people in similar situations, improving accuracy even further.  

The task of measuring, marshalling and deploying the best of ourselves and others at work can be a tricky conundrum, one that personality and psychometric tests are specifically designed to support.

We need to be alert to the pitfalls of personality tests that offer limited scientific reliability or validity, and it’s important to remember that even more scientifically rigorous tests like HEXACO help us to organise personality traits rather than provide a comprehensive theory of our personality – a much more complex task. But, properly used, the right test can give us an important insight into our own default traits and how these can support or derail us as leaders.

When it comes to self-awareness, they offer another tool to help us build a picture of who we are, how we behave and how we might develop and grow.

Test your understanding

• Outline some of the pros and cons of personality testing.
• Explain how the HEXACO model builds on the 'big five' personality traits – and how this might give us a more rounded understanding of personality.