The decision to temporarily withdraw children's heart surgery has put the John Radcliffe Hospital under the spotlight - but not for the first time.

The Oxford hospital has been subject to investigations in the past over the number of deaths linked to such surgery in adults, with concerns raised on a number of occasions.

In a 2007 report into care at the hospital between 2002 and 2005, the Healthcare Commission said improvements were needed.

It highlighted issues over data collection, saying: "Bearing in mind the history of the cardiac unit at Oxford, and the number of questions about the trust's rates of mortality, there had been a surprising lack of robust processes to validate and cross check the completeness and quality of its data."

That investigation was originally sparked by concerns about the then rates of child fatalities in the cardiac unit, raised in an article in the British Medical Journal. An investigation was launched but there were found to be no abnormalities in that field, however.

The hospital had earlier come under scrutiny for its adult heart surgery in the late 1990s when an external review was ordered by the NHS regional office.

Its 2000 report criticised "many aspects of the service", the Healthcare Commission said, including the leadership of surgeons and working relationships between the surgeons.

The trust was monitored until April 2003 after it had been deemed to make "some progress".

The Healthcare Commission noted that the unit had been a "beacon for cardiothoracic surgical services" in the 1980s and that since then, "elements of the service did not develop to meet the needs of their patients".