One reason that dyslexics are drawn to entrepreneurship, Professor Logan said, is that strategies they have used since childhood to offset their weaknesses in written communication and organisational abilities — identifying trustworthy people and handing over responsibilities to them — can be applied to businesses.

William J Dennis Jr, senior research fellow at the Research Foundation of the National Federation of Independent Business, said the study’s results “fit into the pattern of what we know about small-business owners”.

“Entrepreneurs are hands-on people who push a minimum of paper, do lots of stuff orally instead of reading and writing... all of which suggests a high verbal facility,” he said.

Fortune Magazine ran a cover story five years ago about dyslexic business leaders, including Richard Branson, founder of Virgin Atlantic Airways and John T Chambers, chief executive of Cisco.

But Professor Logan said hers was the first study that she knew of that tried to measure the percentage of entrepreneurs who have dyslexia.

Emerson Dickman , President of the International Dyslexia Association in Baltimore said the study’s findings “just make sense”. “Individuals who have difficulty reading and writing tend to deploy other strengths,” Dickman, who has dyslexia, said.