Who are the private patients occupying public beds in public hospitals at the taxpayers' expense? If your income is above average, they are people like you. If your income is below average, there is still a good chance that you could be a private patient.
As you might expect, 83 per cent of households at the highest income level have health insurance. As you might not expect, 11 per cent of households at the bottom income level have health insurance.
Everyone is entitled to virtually free public hospital treatment. Why, then, do we pay many hundreds or thousands of pounds a year for health insurance?
Today's ESRI report finds that more than three-quarters of insurance scheme members see it as a way of "being sure of getting into hospital quickly when you need treatment". That says a lot about unequal treatment when it comes to getting into hospital.
But for those who advocate public hospital care, there is a more depressing finding. When asked why they had health insurance, 77 per cent of those questioned said that "being sure of getting good treatment in hospital" was a very important factor.
There is no hard evidence that this perception reflects reality. But it does reflect a serious loss of faith in the public system.
This is bad because, at the end of the day, you can only join the VHI or BUPA if you can afford to pay for it. Many people are in low-wage jobs and cannot afford private health insurance. Fewer than half of the State's workers are in occupational pension schemes and these people would find it very difficult to pay for private health insurance after they retire.
It is clear that a massive amount of work has to be done to rebuild confidence in the public system. France was recently found by the World Health Organisation to have the best health system in the world. But France spends nearly twice as much on its health services as we do. We cannot conjure our way out of this: if we want a top-class, responsive public health system, we are going to have to pay an awful lot more to get it.
This report is about the use of public hospitals for private health care. One of its more startling findings is that public hospitals get back only half the cost of caring for private patients from insurance companies.
Part of the reason for this is the use of public beds by private patients. Remember that the private patient is not a tycoon arriving at Beaumont or Galway University Hospital in a Rolls-Royce. It's you or me arriving in Accident and Emergency and needing admission tonight. We may end up in a public bed because nothing else is available and we may or may not care.
In this case, the hospital cannot charge our health insurer for accommodation, although the consultant can recoup his or her private professional fees.
A 25 per cent rise in health insurance premiums would be needed to fully reimburse public hospitals for services to private patients. This would have to be phased in, the authors of the report suggest. The chances of this happening, politically, have to be close to zero. It is also unclear that this is the way to go about tackling the core problem.
That core problem is overlong waiting lists and loss of confidence in the system. If we are prepared to spend enough tax money to put these problems right - and that's a big if - then fewer of us will feel obliged to spend increasingly large amounts of money on health insurance.