Pop star Lily Allen was stunned when aides carried out market research into her new songs and received a barrage of four-letter abuse in return.

The Smile hitmaker is gearing up to release her new album Sheezus after a four-year hiatus to start a family, and staff at her record label decided to test the public's reaction to the material by sending out some of her new tunes to focus groups.

They were surprised when they received dozens of foul-mouthed, abusive reviews of the new music, and Allen herself was left mortified when an email containing the critical responses was sent to her.

She tells Popjustice.com, "I accidentally got copied in on a whole bunch of it and reading it was one of the most horrible moments of my life. They don't actually tell the people what it is that they're listening to. So a lot of it was just people going 'is this Lily Allen? It f**king is Lily Allen', 'If this is her I thought she'd f**king retired the stupid c***!' This is about six months ago, too, so it really set things off well. The thing is, people who take part in market research: are they really representative of the marketplace? Probably not."

However, Allen is adamant she not take the critical comments to heart, adding, "I find it totally unhelpful. My mum's a film producer and they do these market research screenings, and more often than not it's just like school - people don't have opinions but because they're asked for them they come up with something and then it becomes a statistic... I'm yet to see an example of market research where it's actually good."