Asia-Pacific nations have been the most successful at containing the coronavirus pandemic, an Australian think tank said Thursday, with New Zealand and Vietnam ranking first and second in their response, with Japan lagging far behind.

The Sydney-based Lowy Institute used publicly available data to evaluate and rank 97 countries and a region in their coronavirus response in the 36 weeks that followed their 100th confirmed case.

Supplied electron micrograph shows the new pneumonia-causing coronavirus. (Photo courtesy of the U.S. National Institute of Allergy and Infectious Diseases)(Kyodo)

Notably, China was not included in the ranking due to what the think tank said was a "lack of publicly available data on testing."

Fourteen-day rolling averages were calculated for six criteria: confirmed cases, confirmed deaths, confirmed cases per million people, confirmed cases as a proportion of tests and tests per 1,000 people.

Data from the six criteria were calculated into a score between zero and 100, with higher scores indicating a better pandemic response.

Top-ranked New Zealand received an average score of 94.4, followed by Vietnam's 90.8. Taiwan and Thailand followed at 86.4 and 84.2, respectively.

Japan scored 50.1 to rank 45th, outperformed by its close neighbor South Korea, which ranked 20th.

Britain, which recently recorded its 100,000th death due to the pandemic, ranked 66th on 37.5 points, and the United States, which has the most confirmed cases and deaths, came to 94th out of 98 with a score of 17.3.

In general, the think tank's analysis found economic status had little overall impact on a countries' response. Although higher per capita income countries had more resources to fight the pandemic, developing countries had more lead time to impose preventative measures.

Conversely, researchers found population size revealed the greatest difference in responses with smaller countries of fewer than 10 million people "consistently outperform(ing) their larger counterparts throughout 2020."

"In general, countries with smaller populations, cohesive societies, and capable institutions have a comparative advantage in dealing with a global crisis such as a pandemic," the Lowy Institute said.