Donald Trump is more of a psychopath than rival Hillary Clinton - and many infamous villains from the past, according to a new study.

Researchers say we are all on the psychopathy spectrum, but have been exploring the traits of the two presidential hopefuls and comparing them to leaders including Hitler and Saddam Hussein.

They used a psychometric tool - the Psychopathic Personality Inventory - Revised (PPI-R) - to get the scores for the presidential hopefuls.

Image: Margaret Thatcher does not appear in the top 20% for psychopathic traits

According to the test, Mr Trump scores more highly than Hitler on psychopathy traits - and just below Idi Amin and Henry VIII.

His overall score of 171 ranks him well into the top 20% of the general population for psychopathic traits.


:: Psychopathic Trait Leaderboard

1) Saddam Hussein - 189

2) Henry VIII - 178

3) Idi Amin - 176

4) Donald Trump - 171

5) Adolf Hitler - 169

6) William the Conqueror - 165

7) Saint Paul - 157

8) Jesus - 157

9) Winston Churchill - 155

10) Napoleon Bonaparte - 153

11) Hillary Clinton - 152

12) Emperor Nero - 151

13) Oliver Cromwell - 136

14) Margaret Thatcher - 136

15) George Washington - 132

According to the Oxford University research, Mrs Clinton also rates in the top 20%, scoring 152.

Dr Kevin Dutton, author of the report and an expert on psychopathy, said that psychopathic tendencies have both positive and negative components - which can support good leadership.

Image: Saddam Hussein scores above Donald Trump

"The PPI-R does not say that someone is or is not a psychopath," he said.

"Both great and terrible leaders score higher than the general population for psychopathic traits, but it is the mix of those traits that determines success."

Dr Dutton points out that several professions attract more than their fair share of those high on the scale.

For example, surgeons, lawyers, the military and politicians all score highly.

Over his decades of research he has contacted the official biographers of many historical leaders.

Image: Even Jesus scored relatively highly - his test was completed by a biographer

To get his scores, he has asked them to fill out, on their subject's behalf, a short version of the psychopath inventory.

For Mr Trump and Mrs Clinton he used an "anonymous, highly respected and seasoned" political correspondent to fill in their scores.

Leaders are rated on "positive" and "negative" psychopathic traits. Positive traits are social influence, fearlessness and stress immunity.

Negative traits are Machiavellian egocentricity, rebellious non-conformity, blame externalisation, carefree "nonplanfulness" and cold-heartedness.

The analysis also reveals that leaders who possess psychopathy's negative traits tend to do badly in office.

Mr Trump and Mr Clinton scored relatively highly on both positive and negative traits, making assessment of their leadership potential difficult.

Image: Donald Trump beats his rival Hillary Clinton in the psychopathy stakes, says the research

Mr Trump outstripped Hitler on factors including social influence and fearlessness, while the Nazi dictator scored higher on cold-heartedness.

Mrs Clinton far exceeded tyrannical Roman emperor Nero on traits such as "Machiavellian egocentricity".

Dr Dutton said: "It is interesting that these scores reflect both the praise and the criticism that Trump and Clinton receive.

"In the end, while both score relatively highly, it will be up to voters to decide if whether their mix of positive and negative traits should send them to the Oval Office or the psychiatrist's office."

Full results of the study will be revealed in an article in the magazine Scientific American Mind.

None of the tests were completed by the individuals themselves.