What about your Minnesota Multiphasic results, or how did you do on your Rorschach test?

The Big Five?

There are dozens of personality tests and assessments with varying degrees of utility.

Which tests are backed by science, and which tests are more entertaining than helpful?

Let's find out.

Dr. Jubbal, MedSchoolInsiders.com.

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and ultimately resigned, but that's a story told on my vlog channel.

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While personality assessments and tests have blown up in the past century, they originated

for a simple purpose – help with personnel selection in the armed forces.

More specifically, the developers of these tests hoped that by studying personality and

potential mental health issues, one would be better able to determine which soldiers

were better or worse suited to fly military aircraft.

Since then, dozens of personality assessments have emerged, each with a different theory

on personality and how to best describe it.

Our understanding of personality and models to describe and approximate it are purely

human inventions, not concrete sciences.

Each system has its own language and ideology, theories and philosophies in determining which

traits are determinative and how to go about assessing them.

How should we categorize traits?

Are they binary or plotted along a bell curve?

While seemingly based in science, few have truly followed any resemblance of the scientific

method.

In fact, most assessments were built on the creators' subjective feelings about personality,

rather than rigorous scientific protocols.

For that reason, most personality tests tell us less about the individuals who take them

and more about the individuals who devised them.

For example, Hermann Rorschach was the Swiss psychiatrist who turned a parlor game into

the iconic inkblot test.

Starke Hathaway was a Midwestern psychologist who found it important to ask questions about

religious beliefs, sex life, and bathroom habits in his Minnesota Multiphasic Personality

Inventory, or MMPI for short.

If you've gotten to your psych rotation in medical school, you've likely heard of

the MMPI-2.

And of course, there's Isabel Myers and Katharine Briggs, the mother-daughter housewife

duo who studied Carl Jung's texts and were inspired to create a personality test despite

having zero background, training, or credentials in anything psych related.

Myers and Briggs are credited for creating the all too famous Myers Briggs Type Indicator,

or MBTI for short.

According to CPP, the publisher of the MBTI, it “measures four pairs of opposing preferences,

which are inborn and value-neutral, to form a person's four-letter type.”

The assessment discerns between “Extraversion (E) or Introversion (I),” “Sensing (S)

or Intuition (N),” “Thinking (T) or Feeling (F),” and Judging (J) or Perceiving (P),”

resulting in 16 different personality types, like ENFP or ISTJ.

A few decades after the birth of the MBTI, a group

of scientists began developing what would become the Big 5 Personality Traits, or the

5-Factor Model.

Rather than relying on their intuition to select criteria for their test, they compiled

every word that could be considered a personality trait and created simple questions about them.

For example, on a scale of 1 to 5, would you say you get upset easily?

Do you follow a schedule?

Based on these answers, the statisticians grouped traits that seemed to cluster together,

such as talkative and sociable, in to five basic categories: Extraversion, Conscientiousness,

Agreeableness, Neuroticism, and Openness to experience.

Chances are that you've heard of Myers Briggs, but maybe you weren't aware of the Big 5

or its more recent derivative, the HEXACO test.

Why is that?

Some suggest its because of the thousands of people who have invested time and money

in becoming MBTI-certified trainers and coaches.

Others say it's because the test focuses only on the positive and therefore it seduces

test takers with an image of their own ideal self.

I argue that the biggest reason for its success is the neatly organized and binary manner

of the test.

There are four categories, each with a binary option.

It's easy to comprehend, easy to explain, and you're able to readily identify with

one of 16 tribes.

As as humans, we love our tribes.

Other personality tests, on the other hand, are not binary and are more of a continuum,

which is less entertaining, less easily understood, and less sexy.

But unfortunately for the Myers Briggs Type Indicator, people and their personalities

are not binary, but are much more on a continuum.

You're not a pure introvert or a pure extrovert, but usually somewhere in the middle.

The insights of the MBTI are comparable to tarot cards or palm reading – being generic

enough such that when you read your description, you can certainly identify with parts of it,

but it's not a truly accurate and comprehensive depiction of who you really are.

When scientists look at such personality tests and assessments, two primary elements come

to mind – validity and reliability.

Validity is a measure of how well a test measures what it claims to measure.

Within validity, there are different types, such as content validity, criterion-related

validity, construct validity, and face validity.

Reliability is a measure of whether the test reliably indicates accurate results, meaning

you would get the same results if you took the test more than once.

Unfortunately for the MBTI, it receives piss poor scores on both fronts.

In one study, researchers found that 50 percent of people received different results the second

time they took the test, even just five weeks later.

Other studies have found similar results ranging from 24-61% of people receiving different

results when taking the test multiple times.

The MBTI misses the mark in a few other ways, including one key element of personality – emotional

stability versus reactivity, meaning the tendency to stay calm and collected under stress or

pressure.

This is one of the most important predictors of individual and group patterns of thought,

feeling, and action.

The judging-perceiving scale reflects whether the test taker is more of a planner or the

spontaneous type, but it overlooks the industriousness and achievement drive that accompany these

characteristics.

Together, they form a personality trait called conscientiousness.

Lastly, in the binary system of the MBTI, traits are mutually exclusive.

For example, under this model, thinking and feeling are on opposite ends of a single spectrum,

meaning that if you are drawn to ideas and data, you cannot also have a preference for

people and emotions.

But research has demonstrated the exact opposite,

that people with stronger thinking and reasoning skills usually also demonstrate better emotional

intelligence, being able to recognize, understand, and manage emotions.

While it's a sad story for MBTI, there's

good news for the Big Five.

The test was shaped by an empirical process and while not perfect, most studies since

have demonstrated more acceptable levels of validity and reproducibility.

So far, studies have demonstrated considerable power in predicting job performance and team

effectiveness.

Some researchers have even mapped the big five to relevant brain regions.

And while the Big Five model is far from perfect, there's growing support for a HEXACO model

of personality, which is essentially the Big Five with an addition of a sixth trait: honesty-humility.

Despite the Big Five being far superior than Myers Briggs from a scientific validity and

reproducibility standpoint, I don't think it will catch on, at least for lay people.

It's just more catchy and easier to say you're an INTP than saying you're 56%

on openness and 35% on neuroticism.

People sometimes expect personality tests to tell them some hidden secrets to their

character.

But the truth is that a personality test can only tell you what you tell it.

Accuracy with the test is entirely based on how honest and self-reflective you are with

your answers.

If I told the test that I'm a super patient and one to readily forgive, it would sure

make me feel good, but I would just be lying to myself.

But I'd argue there's still utility to personality tests, even if they're all far

from perfect.

And sure, entertainment should be one of the top reasons.

Let's be real, including your Myers Briggs on your online dating profile makes for a

good conversation starter.

The real utility is in that it facilitates the process of introspection and reflection.

Taking a personality assessment helps someone consider some of their strengths and weaknesses,

and begin having some important but difficult conversations.

The most insightful realizations I've had in my own behavior, in my own ways of possible

growth, wasn't from seeing the results of a personality test, but from speaking with

close friends and family about areas of improvement.

A personality assessment is by no means a prerequisite, but it can definitely help you get started.

For those who are newer to self-reflection, personality tests can help you consider possible

blindspots.

While Gretchen Rubin's Four Tendencies is far from a perfect model, it helps one consider

what external and internal factors motivate them to behave in certain ways.

I even made a video applying her model to student life, helping you determine how to

understand your personality tendency and use a variety of strategies and hacks to force

yourself into being a better student based on that tendency.

Now were the four tendencies a scientifically valid and reproducible model?

The data is lacking, and I wouldn't put my money on it, but hundreds of comments from

students who successfully implemented and improved their performance is good enough

for me.

Other critics are quick to stay that your personality is fixed and resistance is futile.

It's a waste of effort.

Why even try to change or improve yourself?

Speaking from personal experience, I'd say you have far greater power over your own personality

than you'd expect.

It's just that most people fail to make any significant changes because they don't

put in the proper effort in changing their systems.

In fact, a recent meta-analysis demonstrated that approximately 40% of a person's personality

is due to genetic influence, while 60% can be attributed to environmental effects.

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Thank you all so much for watching.

Do you have any guesses as to what my Myers Briggs Type is?

Let me know your guess down below, and I'd love to hear yours as well!

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