Why has the Wales NHS row erupted?
In the wake of the row over the NHS in Wales over the past week, BBC Wales political editor Nick Servini explains what it is all about.
Why has this row broken out this week, and so fiercely?
The Daily Mail is running a week-long series of articles that are highly critical of Welsh health services - it has splashed it on the front page for three days running.
There have been critical articles in the London-based press previously, but never at such a sustained level by one of the biggest selling papers in the UK.
What is the truth? Is the Welsh NHS performing any worse than in England?
There is no definitive answer to cover the entirety of the NHS.
The Nuffield Trust, which carried out a UK-wide study earlier this year, said there was no evidence to suggest that the Welsh NHS was lagging behind any other part of the UK.
But it has also been said the decision to cut NHS funding in Wales in recent years may be responsible for a "striking" and "disproportionate" lengthening in waiting times.
The Welsh government accepts waiting times are too long for tests and scans, but on many of the other targets and indicators it says no meaningful comparison can be made and in areas like cancer treatment it says the performance is better in Wales.
Why are so many patients travelling from Wales to England for treatment?
There are two reasons why patients from Wales are treated in England: geographic and medical. For example, there are no district general hospitals in mid-Wales so patients have traditionally gone across the border for treatment.
And medically there are specialist services which are only available in some of the larger hospitals in England.
But there has been a big rise in cancer sufferers being treated in hospitals throughout Wales because of improvements in early diagnosis so the rise in cross-border traffic is not proportionately higher than anywhere else.
Is it down to money or the way the health services are run?
Funding has been at the centre of much of the debate.
The Institute of Fiscal Studies said health budgets had been cut by 8.6% in real terms in Wales, deeper cuts than in England and Scotland.
But in the past two budgets set by the Welsh government extra money has been redirected from councils to health. The latest budget allocated an extra £425m for health over the next two years.
The Welsh government has said since 2011 it has protected day to day spending in the NHS, as opposed to capital expenditure which has been cut in line with the reduction in general capital budgets passed on from Westminster to Cardiff Bay.
What does the OECD have to do with all this?
The think-tank is carrying out a study into the state of the NHS throughout the UK.
All the devolved governments, including Wales, have agreed to take part but the Welsh government is refusing to co-operate on the timing.
The English department of health wants to make the findings public in the spring of next year but ministers in Cardiff say if that happens then there would not have been the chance to check the facts.
As a result, it believes the draft results will be used for political purposes by the Conservative-led coalition at Westminster to criticise Labour a matter of weeks before the general election. Instead, it wants more time for the facts to be verified before the results are made known, which means they may not come out until after the election.