Price, who grew up in Luton, had originally forged a career as a pop singer, but found that she was too shy for life in the spotlight and "hated being on stage".
As she accepted her prize, she praised her education at Putteridge High School, a comprehensive in Luton, and criticised the government's attitude towards the arts.
Jude Law, who had presented Price with her award, had earlier criticised the "cultural vandalism" of the new English Baccalaureate qualification, which he said would take "arts, design and music" out of schools.
Price said "It's incredibly depressing listening to the comments people made earlier that a young girl from Luton going to a comprehensive might not be able to imagine being an artist and might not have the opportunities I've had."
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