BBC Health Correspondent Richard Hannaford: "NICE comes into effect on Thursday"

The findings come as the government launches the National Institute for Clinical Excellence (NICE) which aims to ensure patients have equal access to treatment and services irrespective of where they live.

The survey went out to all 122 of the UK's health authorities and boards and asked if they routinely restricted NHS any treatments.

BBC News Online listed a selection of drugs and procedures and asked the authorities' chief executives to add any other treatments restricted.

More than a quarter responded, but some declined, saying that the yes-no response format was too simplistic.

Of those who responded, 50% said they routinely restricted the prescription of beta interferon, the controversial drug for multiple sclerosis.

Seventy-eight per cent said they restricted the availability of in vitro fertilisation treatment for couples who cannot conceive naturally.

And 39% said they restricted surgery for varicose veins.

Institute to establish consistency

The survey offers strong evidence that patients in some areas are being denied some treatments because of financial constraints rather than clinical criteria.

In the case of Beta interferon, some authorities cited clinical reasons for restrictions - but others said its use was budget-limited.

The findings illustrate the variation in health care provision in the NHS depending on where patients live - a phenomenon known as the "postcode lottery" of care among health professionals.

Tough task ahead

BBC News Online's findings suggest NICE will face an uphill struggle to produce uniform guidelines across England and Wales.

Viagra has brought the rationing debate into the public arena

There has been controversy over alleged rationing of the new generation of anti-schizophrenia drugs and not all treatments were available universally.

These have fewer side effects than older versions - in particular they do not cause facial tics.

One of the new drugs - Clozapine - is widely regarded as clinically more effective than predecessors but is more expensive.

Clozapine was restricted by 14% of the authorities. Two other anti-schizophrenia drugs - Olanzapine and Resperidone - were restricted by a further 8%.

Balancing care and cost

The problem, many managers say, is one of balancing clinical effectiveness with cost effectiveness.

This balancing act is one of the key goals for NICE according to the health authority chief executives who responded.

JG Hinchcliffe, chief executive of Rotherham HA, said: "The promulgation of national standards and criteria will be welcomed.

"There is currently such a wide variation in approach across the country. The extent to which such standards are affordable will still be an issue."

Peter Milnes, chief executive of Stockport HA, said he hoped NICE would make the difficult decisions surrounding who should get what treatments.

He said: "It will provide a more coherent and consistent framework within which local clinical decisions or protocols can operate".

Life at a price

Another treatment that was sometimes restricted was Taxol, a drug for ovarian cancer.

Some trials have shown that it can add up to an extra year of life to cancer sufferers, but at £7,500 a year it is regarded as expensive.

Professor Philip Milner, director of public health for Wiltshire HA, said NICE would help authorities balance such pros and cons.

He said: "We very much welcome NICE. We would like national decisions on these difficult issues."

NICE, which will set guidance for England and Wales, can look to Scotland for an example of success, one manager said.

Trevor Jones, chairman of the Scottish Health Board General Managers' Group, said: "Health Boards in Scotland do not restrict treatments for purely financial reasons.

"In considering the introduction of new treatments, both clinical effectiveness and cost effectiveness are taken into account.