The British Medical Journal reported a 15% fall in the number of people who had died at one north London hospital trust using so-called care bundles.

These are checklists covering dozens of conditions including strokes, heart failure and MRSA infections.

The researchers said death rates could be "halved" using the system.

The lists were introduced at North West London Hospitals NHS Trust by its former director of nursing, Liz Robb, who travelled to the US to learn the methods.

She focused on approximately 56 conditions which accounted for about four in five of all deaths at the trust's three hospitals.

Under the system, when a patient is first diagnosed with one of these conditions, a coloured checklist is placed into their medical notes and a sticker on the front tells doctors and nurses to follow it.

Recommended treatments and care are based on the best available medical evidence and even include simple but vital elements such as hand-washing.

For example, any patient with diarrhoea and vomiting would be put in a side room with a closed door and have their antibiotic or laxative prescription reviewed.

Staff would also have to confirm with a signature that they had worn gloves and aprons, used soap and water to clean their hands before and after contact and notify the Infection Control Team.

'Cheap and easy'

At the London trust, which already had better-than-average death rates, there were 174 fewer deaths from the 56 conditions in 2007/08 compared with the previous year - the sharp drop in the overall death rate made it the best-performing trust in the country for that year.

The fact that the sharpest improvement centred on those conditions, and the hospital with the highest use of the checklists, suggested that they played a significant role, said the researchers.

Dr Clare Higgens, the trust's director of medical education, said: "It's so simple to use for doctors, nurses and other clinicians."

"In short, it has worked, and it continues to work."

Professor Brian Jarman, from Imperial College London, one of those involved in the scheme, said the impact could be massive if the system was adopted across the NHS, saving many thousands of lives each year.

Earlier this month he called for 25 trusts to be investigated over apparently high death rates.

He said: "It costs a few hundreds pounds per trust, but we believe it could make a substantial difference - any hospital could take this and say, 'Let's give it a go.'"

"We think an average hospital could halve their death rate."

Inquiries are already coming in from other trusts and the Care Quality Commission, which monitors healthcare standards in England, is also impressed by the idea.

Its national clinical adviser, Professor David Haslam, said: "There is increasing evidence that checklists can make a real difference."

"There is good evidence that they ensure that clinicians don't miss the fundamental elements of delivering patient care and also that teams communicate better with each other."