Families, MPs and support groups have welcomed plans for a review into high death rates among babies treated for heart problems at Oxford's John Radcliffe Hospital.

The Department of Health has announced further work is being done into statistics revealed two weeks ago, which suggested that the Headington-based hospital's cardiac surgeons had a mortality rate significantly higher than the national average.

Further action could be taken following the review, which is being carried out by Thames Valley Health Authority and the Oxford Radcliffe Hospitals NHS Trust, which oversees the JR.

The ORH said it had launched the review to reassure patients and stressed they should have no concerns about its standards of care.

Oxfordshire MPs all agreed further inquiries were needed to back up any claims of wrongdoing.

Oxford East MP Andrew Smith said he was pleased the review had been launched after he sent a letter to Health Secretary John Reid.

Nicky Hunt, 42, of New Road, Bledington, near Chipping Norton, lost her daughter Jade, who failed to survive an operation in 1995 to rectify two holes in her heart.

She said: "This is what we wanted. Until we hear more evidence we can't do any more, but if it's proved that there's something to fight for, then we'll take action."

Fellow campaigner Ros Harrison, 46, of Coombes Close, Shipton-under-Wychwood, was doubtful the review would highlight any wrongdoing.

She and her husband Terry fought in vain for answers after their son Lawrence died on the operating table in 1996.

She said: "They will go through the motions, they always do.

"I am glad that they have been pushed this far though, because at least it shows that they know that people like myself are not happy and they have to do something."

The review will look at statistics produced by the Central Cardiac Audit Database.

The ORH said in a statement: "Thames Valley Health Authority and the ORH are working on a joint review of data on paediatric cardiac surgery compiled by the CCAD, following the opinions expressed in the BMJ, in order to reassure patients that there should be no concerns about the standard of care for children receiving cardiac surgery at the John Radcliffe Hospital."

Thames Valley Health Authority said: "We believe the Central Cardiac Audit Database has robust data. We will be working with the ORH to compare and examine the conflicting data."