Patient perceptions of NHS accident and emergency departments are improving, a watchdog has found, but more action is needed on hospital cleanliness.

A report from the Commission for Healthcare Audit and Inspection found that patients also have "high levels of confidence and trust in staff".

But with continuing concern over the MRSA "superbug", the findings on cleanliness are set to provoke further controversy.

Some 45 per cent of patients rated their emergency department as "very clean", a four percent decrease from 2003.

And 53 per cent of outpatients gave the outpatients department the same rating, a six per cent decrease.

"Some aspects of patients' experience of care in the emergency department have remained the same, or deteriorated," said the commission.

"Patients continue to report high levels of confidence and trust in staff, and to being treated with respect and dignity.

"Information provided to patients on discharge remains a concern, with a substantial proportion of patients leaving the emergency department without information about side effects of medicines, danger signals to look out for and when to resume normal activities.

"Patients' perception of the cleanliness of emergency departments shows a decline: fewer patients report that the emergency department was 'very clean', although the proportion of people reporting that the department was not at all clean has not increased.

"Overall, patients report high and increasing levels of satisfaction with the care received in emergency departments,but there is still considerable scope to improve the information provided to patients."

Anna Walker, chief executive of the commission said the findings were "very encouraging".

"People who are sceptical of the NHS should take note of what patients are actually saying, as it is clear how much they value the services on offer," she added.

"There is much to celebrate but patients still, and rightly so, expect further improvement in their health service.

"Patients are sending a very clear message that they want more involvement in decisions on their treatment and that current standards of cleanliness are still not good enough.  That must improve."

Dave Prentis, general secretary of Unison, said A&E departments "are not going to get 'very clean' status until the NHS employs more cleaners".

"At the very least Unison would like to see the number of cleaning staff go back to pre 1983 levels," he added.

"This is when the Tories introduced compulsory competitive tendering which started the spiral of decline in cleaning staff numbers we have today."