Donald Trump outscores Adolf Hitler on a test used to determine psychopathic traits, while Hillary Clinton ranks between Napoleon and Nero, a researcher at Oxford University has found.

Psychologist Dr Kevin Dutton ranked the psychopathic traits of the US presidential hopefuls and historical figures using a standard psychometric tool – the Psychopathic Personality Inventory – Revised (PPI-R).

Mr Trump did not sit the tests himself but experts on political figures gave their opinions on how he would have scored against the questions to measure PPI-R.

While Hitler scored an overall 169 points, Mr Trump was slightly higher with 171. Margaret Thatcher scored 136 points and Elizabeth I was 130.

Although psychopathic traits are generally seen as negative, in fact some can be beneficial and even Jesus and Saint Paul have appeared high on the psychopathic leaderboard, both scoring 157 points. Politicians and business leaders also frequently demonstrate psychopathic qualities.