One in six NHS staff have experience violence in the workplace and more than three quarters are working more than their contractual hours, according to a survey released today.

Despite those figures the survey also found that the majority of NHS staff have higher levels of job satisfaction than their equivalents in the private sector.

The research, carried out by the Commission for Health Inspection (CHI), found that 73 per cent of staff were happy in their jobs.

This compares to 68 per cent of manufacturing staff surveyed recently by CEP Corporate Performance Project.

The survey, which involved over 200,000 NHS staff across England, is the largest staff survey ever conducted.

Nearly 90 per cent of workers said they had been engaged in some form of training in the last year.

And three in four had spent at least a day on courses provided or paid for by their employer.

Despite the fact that three quarters of staff routinely worked more hours than they were contracted to do 63 per cent said they enjoyed a good work-life balance.

Welcoming the outcome of the investigation, the NHS chief executive Sir Nigel Crisp said: "This survey is impressive. It shows the commitment and passion that NHS people bring to their jobs.

"It shows just how much effort they are putting into improving the health service. They deserve our thanks and our support."

And he added: "It is vitally important that our workforce are properly trained, protected and supported so they can give the best possible care to patients."

But he stressed more would be done to rectify the problems outlined in the survey.

"This is what we are working to do. We have a big increase in staff year on year. We have good training and development programmes, and we have a zero tolerance approach to violence against staff," said Sir Nigel.