The NHS provides Britons with the most widely accessible treatments among 11 leading industrialised nations studied by an American think-tank.

It also delivers high-quality care at low cost among rich nations, according to the survey by the Commonwealth Fund.

The UK is the only one of the 11 countries where wealth does not determine access to care, the study found.

It showed that a third of American adults “went without recommended care, did not see a doctor when sick, or failed to fill prescriptions because of costs” - but this figure was only 6% in the UK and 5% in the Netherlands.

About 70% of British patients reported same or next-day access to doctors when sick, less than the 93% of Swiss adults reporting rapid access. In contrast, however, only 57% of adults in Sweden and the United States, and less than half in Canada and Norway, were seen this quickly.

The NHS was also extremely cost-effective, with spending on health per person almost the lowest in the survey. Only New Zealand, where one in seven said they skipped hospital visits because of cost, spent less per head.

Nigel Edwards, acting chief executive of the NHS Confederation, said the report was a “good result” for the UK. He added: “The issue in many other nations is that you buy insurance to cover for the price of expensive drugs or that you need co-payments on hospital treatment.”