Lionel Shriver has won the BBC National Short Story Award 2014 for her story Kilifi Creek.

This was the third time Shriver had been shortlisted for the award, and last night she picked up the £15,000 prize at the ceremony held in the BBC’s Radio Theatre in London.

Chair of the judges, BBC creative director and presenter Alan Yentob, said: "From a fantastic shortlist, Lionel Shriver's Kilifi Creek stood out as a wonderful evocation of life in miniature, crossing continents and generations. She is a worthy and deserved winner in an exciting year when the short story has taken centre stage. Shriver proves that short really is sweet and it's never been sweeter than now."

An American writer who lives in London, Shriver is the author of 11 novels. She is best known for the international bestseller, We Need to Talk About Kevin. When asked about tackling short stories rather than novels, she said: "I love working in a form that doesn't consume a couple of years. Ironically, low temporal risk can facilitate high-risk style and content. In a short story, you can try anything."

Zadie Smith was this year's runner-up, receiving £3,000 for her story, Miss Adele Amidst the Corsets, in which an ageing American performer comes face-to-face with a multitude of resentments while buying undergarments on the East Side of New York City. Smith is the author of the novels NW, White Teeth, The Autograph Man and On Beauty.

The three other shortlisted authors, Tessa Hadley, Francesca Rhydderch and Rose Tremain, received £500.

Shriver's winning story was first published in The New Yorker in 2013. It is the story of Liana, a young and thoughtless gap-year traveller, outstaying her welcome as a house guest in Kenya – whose brief encounter with mortality in a treacherous African river is a painful coming-of-age shock. We meet her again years later in New York leading a more conventional career and continuing to cheat death – for now. Wry, witty and understated, it is a masterly meditation on how we react to what life might have in store for us.

Shriver said: “I have a little collection in my head of the occasions on which I almost died. Some of these are dramatic, but in others, to an observer, nothing would have occurred. For these are experiences of what didn’t happen. But I have a keen sense of the ‘counterfactual’, as one critic observed, which is only by way of saying I have some imagination, some appreciation for how at numerous junctures I might have veered in a different – in some cases, fatal – direction.”

She added: "What makes the near-miss catalogue so haunting is awareness that at some point, as the text observes, 'there is no almost'. So when I read a story in the NY Times about a young woman who plunged to her death in Manhattan, just because a railing of her apartment balcony came loose, I was moved to write Kilifi Creek. That young woman emblemized the 'no almost'."

Readers can listen to the BBC Radio 4 broadcasts of Kilifi Creek, Miss Adele Amidst the Corsets and the three other shortlisted stories read by five UK's top actors, including Carey Mulligan and Rebecca Hall, at bbc.co.uk/podcasts/series/nssa for up to 30 days after their first airing. The BBC National Short Story Award 2014 Anthology is published by Comma Press.