The survey of 1,000 NHS doctors, sponsored by Computer Weekly, raises questions about the project's success and adds weight to calls for a published independent review of the £12.4bn scheme.
It found that 23% of GPs and 35% of other doctors supported the aims of the NPfIT, compared with 56% and 75% in 2004. Seventy six per cent said it was important to have an independent review of the NPfIT.
The falling support from doctors is a worry, said professor of software engineering Martyn Thomas, a spokesman for 23 academics campaigning for a review of the NPfIT.
"This is not good news for the project because without this support it cannot possibly succeed. It is serious and depressing that support is falling as the project progresses. You would expect this to rise as the project goes forward," he said.
The Medix report said, "Five years after it began, doctors still support the principles of the project, but most are critical of its costs and believe it is being poorly implemented."
The survey found that less than 50% of doctors believe the NPfIT is an important NHS priority, compared with 80% in February 2003.
Comments from those surveyed suggest that management mistakes and spiralling costs have led to disenchantment among doctors.
"Computerisation of the NHS is inevitable, and if it works well I am in favour of it. But many good ideas have floundered on computerisation, and huge sums have been wasted by government on some projects," said one doctor.
Angela Eagle, exchequer secretary to the Treasury, told parliament last month that the NPfIT was a success. "Without the programme, the NHS could no longer function, and it is already providing essential services and significant benefits to tens of thousands of clinicians and millions of patients. It is therefore a success story that ought to be acknowledged," she said.
A spokesman for NHS Connecting for Health, which runs the NPfIT, said it consults with a wide range of clinicians in the development of systems and in their use.
"In the light of wider experience and evidence, the results of the Medix survey do not appear to reflect the general picture on the ground or chime with other recent comprehensive surveys," he said.