An 11-year-old brainbox from west London has achieved the top possible score in her Mensa IQ test.

Anushka Binoy, of Isleworth , scored 162 to gain membership of the exclusive society, where entry is reserved for Britain's brainiest 2%.

The average IQ is 100 and a score of over 155 on the Cattell III B scale puts you in the top 1% of the population.

Proud father Binoy Joseph said he always knew his daughter was smart but hadn't realised quite how remarkable.

"She loves reading quite advanced books and she memorises a lot of what she reads, so I knew she was pretty special but I was amazed when we got the results back. We're very proud of her," he said.

Anushka Binoy's acceptance letter from Mensa
Anushka Binoy's acceptance letter from Mensa

He added that Anushka, who attends St Mary's Catholic Primary School, in Isleworth, is no swot, with tennis, swimming and playing the violin among her hobbies.

Age should be no barrier to a high IQ, with the test modelled to take account of both youthful inexperience and diminishing speed as people get older. The youngest member of British Mensa is just two-and-a-half and the oldest was 103.

A Mensa spokeswoman said it did not keep a record of members' IQs so it was impossible to say how rare an achievement this is, but she said it was certainly "exceptional".

In September, we reported how 56 pupils from The Heathland School in Hounslow had been accepted by Mensa after they were selected by teachers to sit the exam.