Plath's book is essentially a fictional novel however when one draws comparisons between Plath and her heroine Esther Greenwood, it is obvious that "The Bell Jar" is, to a large extent, autobiographical. Nonetheless, Plath was an established writer - almost wholly of poetry - and this shows through in the book. Kaysen, on the other hand, was not a professional writer and, similarly, this shows through in her book. Although "Girl, Interrupted" is autobiographical, Kaysen's style deviates from this at times. She doesn't necessarily explore events in chronological order, sometimes jumping back and forward between situations.
The tones in which Plath and Kaysen wrote their books differ quite considerably. Kaysen has successfully injected some humour into a book on a fairyl serious subject; granted this humour is usually quite dark and almost sarcastic. "The Bell Jar" displays little - if any - humour and is instead very serious, a tone in-keeping with Plath's poetry.
Both have achieved great praise and acclaim but the truth of the matter is that if Kaysen's "Girl, Interrupted" were a work of fiction as opposed to a memoir it seems unlikely that it would have been nearly as popular due to Kaysen's erratic and often inconsistent style of