A fascia-sensitive test should be introduced to the planning process because consumers want a wider choice between different retailers, according to the Economic and Social Research Council.

A survey of 2,000 consumers for the government-funded body indicated that Tesco was by far the grocer people most wanted in their area, with Sainsbury's second choice, Asda third and Morrisons fourth.

But the highest levels of satisfaction were found in areas where Tesco was operating only as part of a varied mix of stores locally.

"One of the big things we have found is that consumers want variety," said Professor Ian Clarke of Lancaster University Management School, which conducted the research. "People want a Tesco and an Asda, not two Tescos."

The research also indicated that poorer consumers living in deprived areas were unhappy with their level of access to supermarkets, even in towns with a choice of three superstores.

Three stores is the minimum number that the Competition Commission believes is adequate provision for a town.

"The research shows consumers' local and personal circumstances are major factors in determining their satisfaction with local retail choice," said Clarke. "But these aspects have largely been ignored in debates."

The study had been submitted to the Commission's grocery inquiry, said Clarke.