The Healthcare Access and Quality Index (HAQ), published in the UK journal The Lancet on Thursday, studied the quality of healthcare in 195 countries by measuring mortality rates from causes that should not be fatal in the presence of effective medical care.
The study analyzed death rates from 32 such diseases and conditions over the period 1990 to 2015 and found that nearly all countries saw their rating improve over the years.
Spain scored 90 points out of a maximum 100, placing it eighth in the world rankings, above the healthcare systems of Italy (89), France (88), Greece (87), Germany (86), the UK (85) and Portugal (85).
Andorra topped the Index with a score of 95, followed by Iceland (94) and then Switzerland in third place on 92 points.
Sweden and Norway made up the top five and 13 of the top 15 countries were in Western Europe, joined by Australia (6th) and Japan (11th).
The UK placed 30th and the US 35th.
At the bottom end of the table was Central African Republic on only 29 points.
The average score across the board improved from 40.7 points in 1990 to 53.7 in 2015, and 167 out of 195 countries “significantly increased” their HAQ rating during that time, said the study.
Inequalities had widened, however. The gap between the leading country and the last was 62 points in 1990 and 66 points in 2015.
The study also compared the HAQ scores to countries' level of development on the so-called socio-demographic Index (SDI) and found that some, such as the US and South Africa, achieved a healthcare quality and access rating that was lower that what should be expected for a country of that level of development.
This is a “warning sign that heightened healthcare access and quality is not an inevitable product of increased development,” said the study.
If every country had reached the maximum HAQ for their level of development, the average result would have been 73.8 in 2015, 20 points higher than what was actually achieved, “a clear indicator of untapped potential for healthcare improvement worldwide,” said the study.
Some, however, achieved higher than expected levels of healthcare in 2015, including Peru, the Maldives and Ethiopia.
South Korea, Turkey, China also recorded large improvements over the years.
Spain scored the maximum points (100) in its treatment of diptheria, tetanus and measles and just one short of the perfect score when it came to maternity and respiratory treatment.
It's lowest scores were in treatment for Hodgkins Limphoma (64 points), Leukemia (66), gallbladder disease (74) and skin cancer (74).
Spain has both public and private healthcare systems with free basic healthcare provided to those who contribute to the Spanish social security system and their families.
An estimated 19 percent of the population holds private health insurance, which can either be used as a supplement or an alternative to public care.
Spain is the global leader in organ donation, carrying out more transplants per capita than any other nation in the world and has the highest life expectancy in Europe.