NHS staff who highlight bad practice face problems at work as a result, according to a survey by Unison.

One third of employees who reported problems to senior staff faced "some personal comeback" according to the study published on Wednesday.

And almost as many respondents felt that their NHS trust "would not want to be told there was a major problem".

Half of those questioned said they were unaware of any formalised whistle-blowing procedures, while three-quarters felt there had been no improvement in the hospital "culture" in terms of reporting problems.

Complaints about unsafe staffing levels and government targets or waiting list goals were felt to be the least easy to report. The results of the survey are likely to be a cause of embarrassment to the government, as staff have been encouraged to report problems in order to improve service delivery.

Karen Jennings, Unison's head of health, said the current situation was "unacceptable" and that ministers needed to help staff who were "trying to respond to central government policy".

"The government have introduced a number of key initiatives designed to make whistle-blowing work and yet it is clear that somewhere along the line, this information is not getting through," she said

"There is a reality gap between what the government is trying to achieve and what is happening on the ground."

Despite these problems, the survey found that 90 per cent of staff were willing to blow the whistle when they had concerns about patient safety.

One third of health workers felt that bosses would want to know their concerns even "if it resulted in bad publicity".

And half of the staff who had complained said their concerns had been reasonably dealt with.

"It is essential for staff to be able to raise concerns about standards of patient care or staff safety without the fear of reprisals. Employers must have clear whistle-blowing policies open and easily accessible to everyone," said Jennings.

"It is simply appalling that staff say are victimised if they blow the whistle on bad practice in the NHS. This is dangerous thinking and trusts are failing in their duty of care to patients and staff by burying their heads in the sand over this issue," she added."Introducing a whistle-blowing policy makes sense and whistle-blowing must be promoted across the entire NHS including trusts, executive agencies, private contractors and PFI hospitals."