GPs have yet to vote on the contract

Researchers have found that doctors are almost evenly divided over whether the proposed changes will encourage them to stay in their jobs.

They are also split on whether the contract will have any benefits for patients.

The findings come as it emerged the British Medical Association has decided to postpone a nationwide ballot of GPs.

Clearly individual GPs cannot support funding arrangements that threaten the viability of their own practices Dr John Chisholm

It follows concerns from some GPs that they will lose money if they accept the new deal.

Details of the contract were published last month after two years of negotiations between the BMA and NHS managers.

The deal, if accepted, will pave the way for major changes to the way GPs work and to the way primary care services are provided.

Income cut

Last month, the BMA predicted it could also see pay increases of up to 50% for some of the top GPs.

Overall spending on primary care is set to rise by 33% over the next three years, as part of the deal.

But some GPs have told the BBC that the deal would actually cut their income.

Dr Pritt Buttar, of Abingdon, said his practice could lose �140,000 a year. "It would be a complete meltdown, the surgery simply could not function," he said.

Dr Bruce Alan, of Worthing, said: "It means that we will be unable to invest in improving our services. We will simply carry on like hamsters on a wheel, and as demand goes up services will probably deteriorate."

Dr John Chisholm, chairman of the British Medical Association's GP Committee, said the formula behind the new contract was intended to allocate funds to practices based on patient need.

"But clearly there is a huge problem here. Most GPs have been very supportive of the shape and philosophy of the contract, but clearly individual GPs cannot support funding arrangements that threaten the viability of their own practices."

Dr Chisholm said negotiations would continue with the NHS Confederation, which is representing the government, to try to ensure that high quality GP practices were not de-stabilised by the new arrangements.

Survey results

The survey of 50 GPs from across the UK by Isis Research found that 47% believed the deal would encourage them to stay in the NHS. However, 40% said it did nothing to encourage them to stay.

Similarly, 40% said they believed the proposed changes would have positives benefits for patients. Forty-three per cent said they would not.

The GPs also criticised the contract for failing to ensure doctors had time to keep up-to-date and maintain their skills. Four out of five said the changes would not enable them to devote more time to education.

A rejection of the new contract by GPs would be damaging to both the BMA and the government. Both are still reeling from last year's rejection of new working arrangements by consultants.

Tom Marshall, NHS analyst at Isis Research, said the findings showed that the proposed changes could actually demoralise GPs.

"The new GMS contract is very ambitious in line with other recent government policies and seems to be laden with rewards and punishments which could actually see GPs morale decreasing further due to lack of development potential."