Now we have proof.

Beyonce Knowles' fans are dumb.

Admirers of the 'Crazy in Love' singer came out second from bottom in a 'Music That Makes You Dumb' study in the US, which compared students SAT results - a standardised test taken by all American students hoping to go to college - with their favourite music.

US rapper Lil' Wayne was the only artist whose fans scored a lower average in their SAT tests according to the poll, while classical fans scored higher than anyone else.

Fans of indie music were credited with above average intelligence with fans of bands like Radiohead, Counting Crows and U2 scoring highly in their SATs.

Virgil Griffin, the creator of the 'Music That Makes You Dumb' study and its accompanying website, said: "I've listened to artists and afterwards thought to myself, 'Wow... loving this rubbish says a lot about someone and how much they've got going on in their head.'

"Could one's musical tastes say something about intelligence? How about SAT scores? Well, like any good scientist, I decided to see how well my personal experience matches reality."

Although the results put mainly urban artists at the bottom, fans of rock bands such as Aerosmith, Nickelback and The Used all scored low in the graph.