A television campaign to promote reading has managed to boost sales of DVDs of the stories instead.

The winner of the BBC's Big Read will be revealed tonight but rather than thumb through pages of print, it seems more people would rather sit back and watch a dramatisation of their favourite novel.

Sales of the 21 shortlisted books have shot up by up to 450%, but sales of adapted TV and movie versions have gone up by three times as much.

The paperback version of Captain Corelli's Mandolin saw sales rise by 155% after the Big Read, but the Hollywood film adaptation starring Nicolas Cage rocketed by 1,533%.

Joseph Heller's cult novel Catch 22 increased in sales by just 24% after being featured on the show, while sales of the 1970 Mike Nichols movie went up by 1,500%.

Ray Johnson, professor of film heritage and documentary at Staffordshire University, said that the figures reflect a trend toward a "couch potato culture".

"A DVD is like a frozen ready meal. It serves up the concept straight away and is easy to digest. Reading a book on the other hand is like a gourmet meal that demands participation and is a lot more enjoyable."