Pints of lager, Ben Sherman shirts and traditional pubs are at risk of being crowded out in a nightlife style revolution in British city centres, according to new academic research.

The growth in style bars with upmarket decor and prices to match is threatening not only the Geordie night out - a marathon of stand-up drinking, party anthems and kebabs - but is also squeezing out local entrepreneurs and choice, warn researchers from Newcastle University.

Nightlife activity in licensed premises is an important element in the transformation of British city centres in recent years into more vibrant places to live, work and be entertained, they say.

But the study into the city centre nightlife economy of Newcastle, Leeds and Bristol warns that the growth of style bars driven by national chains and reflecting the rise in female and white-collar employment, threatens to exacerbate social exclusion.

It could also, suggest the researchers, mean the loss of an opportunity for young entrepreneurs to gain a foothold in a dynamic sector. The pub and club industry has an annual turnover of around Pounds 22bn, equal to about 3 per cent of national gross domestic product.

Social exclusion, says researcher Robert Hollands, goes beyond issues of cost and taste. The research team, whose two-year Pounds 117,000 study was funded by the government's Economic and Social Research Council, found examples in Leeds of would-be drinkers being denied access to premises for wearing the wrong labels on their clothing. The future gatekeepers of licensed city centre premises could, he suggests, be "style pickers" rather than bouncers.

The researchers, who are publishing separate studies into Newcastle, Leeds and Bristol, say the growth in stylish bars owned by national chains was evident in all three.

Mr Hollands, a senior lecturer in sociology and social policy, recommended steps to avoid cityscapes becoming "Anywheresville UK" brandscapes. These include flexible licensing hours - more widespread in Leeds and Bristol than Newcastle - and steps by local authorities to help provide affordable premises for local entrepreneurs. "Diversity is the lifeblood of cities," he says. "We are saying open things up but give special regard to local operators."