Britain's National Health Service, or NHS, is facing a growing shortage of family doctors, even though they are among the best paid in the Western world, a major report has found.

According to research by the Organization for Economic Cooperation and Development, or OECD, the United Kingdom has the second-lowest number of doctors relative to its population when compared to other leading European nations.

The United Kingdom has only 2.8 doctors per 1,000 people, compared with an average of 3.5 doctors across the OECD. The UK shortage is second only to Poland.

The OECD conducts research on economic and social policies; its 36 member countries have the world's most advanced economies.

Despite this, the study shows that family doctors, known as general practitioners, or GPs, now earn more than three times as much as the average employee in the UK, or more than 100,000 pounds ($130,000) a year.

The report reveals only Germany pays its GPs more than Britain when compared with the rest of its citizens, yet the UK is struggling to hold on to its family doctors.

The Daily Mail reported that the practices of some 270 GPs in England closed last year because it became impossible to staff them－reducing the number of operating medical offices to the lowest level since records began in 1995.

Rising numbers of doctors are taking early retirement, prompted by a growing pension crisis, according to The Daily Telegraph. It said almost 1,000 GPs and hospital consultants opted to retire last year, compared with 384 a decade ago.

The OECD report examined data between 2000 and 2017 that highlighted the UK's reliance on foreign-trained medics. Almost 29 percent of doctors practicing in the UK had qualified abroad, the fifth-highest figure in Europe.

The research also showed growing dissatisfaction among patients in the UK with how long their appointments lasted; 84.9 percent were satisfied with the amount of time allowed for their consultation, down from 88.8 percent in 2010.

Experts said they fear for the future of general practice in Britain as the number of medical offices in operation hits an all-time low.

Gaetan Lafortune, an OECD health expert, told the Mail: "The differences between the UK and other countries are very striking, particularly when you look at how many GPs are leaving the profession much earlier than in other countries."

The findings follow a separate report by British health experts released earlier this year.

It concluded the NHS would never recover from its chronic staffing shortages and warned that "radical changes" regarding staffing are necessary. The report by the King's Fund, Nuffield Trust and Health Foundation said: "The shortfall in the number of GPs is so serious that it cannot be filled at all. The only way forward is to use the skills of other staff, including pharmacists and physiotherapists, much more widely and routinely in and alongside general practice."