05/10/2016 11:20 AM AEDT | Updated 06/10/2016 11:38 AM AEDT

Why We Need To Stop Classifying People As Type A Or Type B

It's not as simple as it sounds.

Type A or Type B... or somewhere in between?

"You're so Type A".

Has someone ever muttered these words to you and you've nodded along, not realllly knowing what 'so type A' really means?

It's a concept that has stirred psychologists and individuals alike for decades.

A major problem is that it assumes that people fall into one category or the other... In reality, most people are probably a blend of somewhere in the middle.

The term "Type A" was developed by a cardiologist named Meyer Friedman in the 1950s as a way to measure cardiovascular health.

"He noticed that patients with heart disease seemed to be different in terms of their personality when compared with average individuals," Dr Luke Smillie, Senior Lecturer in Personality Psychology at the University of Melbourne, told The Huffington Post Australia.

"He came up with this idea that there were two broad personality types: Type A were people who were more competitive and driven, whereas Type B people were typically relaxed and easy-going."

"Following 10 years of testing, it was predicted that people who had these Type A characteristics would have a higher risk of developing coronary heart disease."

The theory became popularised when Friedman's book Type A Behaviour And Your Heart, written with Dr Ray H. Rosenman, was published in 1974, later becoming a best seller.

Decades later, the concept model has evolved into a loose parlance of tendencies related to highly- competitive people.

For starters, we've broken it down for you:

Type A:

Ambitious -- with a strong drive to succeed

Time-urgent and always on the go

Potentially hostile and easily agitated -- with a tendency to react to daily stresses

Impatient and aggressive

Type B:

Less ambitious -- less tendency to try to be successful, but instead enjoys successes as they come

Relaxed and easy-going nature

More personable and sociable

Creative and predicatable with a steady personality

So, which type are you?

Wondering which side of the spectrum you fall on?

It doesn't really matter.

"One of the main problems with this theory is that it assumes people fall into one category or the other -- so you are either Type A or Type B," Smillie said.

"In reality, most people are probably a blend of somewhere in the middle."

Type A people tend to have a serious phobia of wasting time.

"Over many decades, there has not been sufficient evidence to prove that there is some kind of psychological characteristic or trait of personality that varies as a type. It's more a matter of degree."

Smillie loosely defines the Type A concept as a stereotype.

"The Type A concept lumps together several personality traits that don't really go together.

"Sure, some people may have all those characteristics, but they may not be all as important as one another -- particularly when you look at it from the perspective of understanding heart disease."

From this perspective, hostility is one trait that can be particularly problematic.

"People who have higher hostility tend to react to and have a higher response to stresses in their life. That seems to be the factor that explains why those individuals have a higher risk of heart disease."

Getty Images/OJO Images RF
Recognising your tendency to become hostile or agitated is a good place to start.

The theory today

The Type A/B model remains an accepted personality theory -- with some identified flaws -- that can be used to identify individuals' strengths and weaknesses.

According to Dr Smillie, it can lead us down the path towards positive psychological change and self-help.

"If you identify yourself as a Type A person because you are driven or competitive, it may not be those elements that you look to work on," he said.

"It becomes more useful when a person tends to become quite frustrated or provoked quite easily."

Something to work on, people.

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