North Devon District Hospital used to have a three-star rating

The trusts covering the Royal Cornwall and North Devon hospitals were regarded as "weak" for both categories.

Elsewhere, the Plymouth Hospitals NHS Trust was said to be weak for its finances, but fair for services.

Hospital bosses at all three trusts said they were working with the commission to make improvements.

The quality of clinical care that patients are receiving every day is extremely good. Professor Colin Roberts, Royal Cornwall Hospital's Trust

The Healthcare Commission's new ratings replaces its old star rating system. Hospitals' facilities are rated in a scale ranging from "weak" to "excellent".

Just 9% of hospital trusts nationally were rated as "weak".

The North Devon Hospitals Trust, which used to have three-star status under the old system, is reassuring patients that its levels of care have not changed.

Director of Nursing Carolyn Mills said: "The services people have received over the past year, which we have generally received very positive feedback from the majority of patients, has not changed; and the clinical care is not affected by this rating."

In Cornwall, the chairman of the Royal Cornwall Hospitals Trust, Professor Colin Roberts, said there was no doubt that staff were committed to delivering high standards of care.

Care levels

He said: "We know the quality of clinical care that patients are receiving every day is extremely good.

"The assessment result is more about the need to strengthen the processes that determine and show how that level of care is maintained."

He said managers were working in partnership with the commission and had already implemented an action plan of improvements.

The Plymouth Hospitals NHS Trust, which manages Derriford Hospital, the Royal Eye Infirmary, Mount Gould and at the Child Development Centre, said it met 38 out of the 44 parts of the core standards and 10 of the 13 existing national target indicators.