They all took psychology tests to measure their levels of narcissism, which the study defined as ‘a pervasive pattern of grandiosity, need for admiration, and an exaggerated sense of self-importance’.

Those who scored higher on the narcissism test checked their Facebook pages more often each day than those who did not.

There was also a difference between men and women – men generally promoted themselves by written posts on their Facebook page while women tended to carefully select the pictures in their profile.