The book is a stream-of-consciousness account of an abused young girl who goes off the rails. Reviewing it in the Guardian, Booker prize-winning writer Anne Enright described McBride as "that old fashioned thing, a genius, in that she writes truth-spilling, uncompromising and brilliant prose that can be, on occasion, quite hard to read."
Tim Parnell, head of English and comparative literature at Goldsmiths College and chair of the judges, said A Girl is a Half-formed Thing was a "boldly original and utterly compelling" novel. It was "just the kind of book the Goldsmiths prize was created to celebrate … Serious discussion of the art of fiction is too often confined to the pages of learned journals and we hope that the prize and the events surrounding it will stimulate a much wider debate about the novel."
The prize was set up by Goldsmiths' College with the New Statesman magazine to reward fiction "that breaks the mould or opens up new possibilities for the novel form".
McBride completed the first manuscript for her novel nine years ago, in the space of just six months, but was rejected by publishers. She later submitted a revised manuscript that was signed up by independent publisher Galley Beggar Press, run by the Guardian's Sam Jordison.
A total of 123 novels were entered for the award, before the pile was reduced down to a shortlist of six: Harvest, by Jim Crace (Faber & Faber), Exodus, by Lars Iyer (Melville House), Red or Dead, by David Peace (Faber & Faber), Artful, by Ali Smith (Penguin) and Tapestry, by Philip Terry (Reality Street).
Parnel praised all of the shortlisted books as "strikingly original", and said that "all of them refuse the ready comforts of convention. Making full use of the resources and possibilities of the novel form, each writer has found the distinct idiom that their story demands."
The inaugural Goldsmiths prize judges, along with Parnell, were novelist, playwright and critic Gabriel Josipovici, Jonathan Derbyshire, managing editor of Prospect Magazine, and Nicola Barker, a Granta Best Young British Novelist 2005.