Data on hospital heart surgery survival rates is being published.
But the information is not compiled
individually for all the surgeons. Why?
Heart surgery details are being published
How has the data been compiled?
The Healthcare Commission asked each hospital with a heart unit in England and Wales to provide data on its survival rate.
This was measured as whether a patient was ever discharged from hospital.
A figure for what the expected survival rate should be is then calculated. This was done using a range of factors including age, health of the patient and the type of surgery to determine just how likely it would be that a patient would live.
Doctors have long-argued that the most experienced surgeons take on the most complex cases and, therefore, are likely to have a lower survival rate.
In some cases - for 17 hospitals - surgeons have also provided data individually.
Is this the first time this data has been published?
This is the fullest account of heart surgery survival rates to date, but there has been a gradual drip feed of information over recent years.
Two years ago, the Society of Cardiothoracic Surgeons produced data on two set types of surgery on a unit-by-unit basis.
Other trusts have also published data either voluntarily or because they were challenged under the Freedom of Information Act.
In August last year, St George's Hospital in south London published performance data for all 20 of its specialities, taking into account risk factors. It was the first NHS trust to do so.
Why isn't the data broken down surgeon by surgeon?
There has been much debate - even with models in place to take into account risk factors - about how the data will be used.
Patients, and eventually the government, have been pushing for greater transparency ever since the Bristol Royal Infirmary scandal, when surgeons were found to have continued carrying out heart operations even though they had higher-than-average deaths.
Some surgeons believe publishing individual data will lead to patients shunning certain professionals and thus put pressure on doctors to avoid the riskiest cases.
However, others have argued it is better to be open and transparent to boost public confidence in the speciality.
Is there any evidence to suggest risky surgery is avoided?
It is too early to tell among the trusts which have published data in England and Wales.
A study in the US last year found where individual data is published surgeons avoided carrying out "potentially life-saving" treatment on the most risky patients because it could skew their death rate.
Of the 120 physicians who responded to the survey, the vast majority agreed or strongly agreed that the publication of mortality statistics has, in certain instances, influenced their decision regarding whether to perform angioplasty on individual patients.