How much adaption is adaption for graphic novels?

[Cait]

As a general rule, we separate graphic novels from the books which they adapt just like we separate radically abridged books. However, I was looking at Ted Dekker's books this afternoon and wondering about this -- Dekker has a number of novels which have also been adapted as graphic novels, but I had to dig into cataloging records to find the adapter and artist names: the graphic novels are strongly branded with Dekker's name and appear to follow the originals quite closely. It makes me wonder if perhaps in the case where the graphic format is downplayed so far that the artist is barely credited we should just combine the novel and the graphic novel.

[Michael]

Can't say I've ever seen a graphic novel that retained more than 5% of the original text. I know there are some mainly text adaptations with very limited illustration but I wouldn't class them as a graphic novel in the first place. I recently read a graphic novel adaptation of Fyodor Dostoevsky's Crime and Punishment (Illustrated Classics)strongly branded with Dostoevsky's name but readable in under an hour and with about 1% of the original text - it was also reworked into a contemporary setting with the detective using a laptop and the story containing many modern substitutions. I noticed it had been lumped in with the original book so I seperated it, left a note giving my reasons but it soon got recombined. Personally I would only seperate or combine graphic novel adaptations if I'd read both works and felt that a substantial amount of the text was included and that it had not been reworked in some way.
I've not read the Ted Dekker material so I can't really add any input in that specific regard.

[This Is Not The Michael You're Looking For]

What about the reverse case? Books which started as graphic novels but were later "novelized"? There aren't as many of these, but I can think of one or two off the top of my head and I suspect there are others.