Humans still make better surgeons than robots, carrying out operations in a shorter time yet making no more mistakes, a new study suggests.

Robotic surgery has increased substantially in the NHS since the first machines were installed a decade ago, and is commonly used for prostate, bladder and kidney removal as well as for cutting out tumours.

It was hoped that robots would be more accurate, dexterous and quicker than humans, but a new study has shown that they do not improve outcomes for patients, and operations take longer.

Researchers at Stanford University School of Medicine in the US reviewed nearly 25,000 operations across 416 American hospitals between 2006 and 2012.

They found that just 28 per cent of kidney removal patients who had keyhole surgery performed by a human surgeon were under the knife for more than four hours, compared to 46 per cent of those who were operated on robotically. Robotic surgery was also around £2,000 more expensive per patients.