Washington (CNN) - President Donald Trump and his administration have been criticized over the rate of coronavirus testing in the US, but on Wednesday, he claimed the US had done more testing than any other nation.
At a press briefing a day earlier, Dr. Deborah Birx, the White House's coronavirus response coordinator, told reporters, "We now have 370,000 tests that have been done. The majority of those -- over 220,000 in the last eight days, which, those of you who have been tracking the South Korea numbers, put us equivalent to what they did in eight weeks that we did in eight days."
Less than a day later, the President tweeted: "Just reported that the United States has done far more 'testing' than any other nation, by far! In fact, over an eight day span, the United States now does more testing than what South Korea (which has been a very successful tester) does over an eight week span." He reiterated this claim multiple times in a press briefing Wednesday evening.
Facts First: While the US has overtaken South Korea in total numbers of coronavirus tests administered, it has conducted far fewer tests per capita given the US population is more than six times larger than South Korea's.
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"Yes, it is true that South Korea has run less tests as an absolute number. However, it is important to point out the huge difference in the population sizes," Aubree Gordon, associate professor of epidemiology at the University of Michigan, told CNN.
As of Wednesday, South Korea, which has a population of 51 million, had conducted 357,896 tests, based on reports from the Korea Centers for Disease Control and Prevention.
Comparatively, the United States, with a population of 329 million, had administered at least 418,810 tests, according to the Covid Tracking Project, a group led by Alexis Madrigal, a staff writer for The Atlantic magazine, with more than 100 volunteers that compiles coronavirus testing data from state government websites and government officials.
But because, as the Kaiser Family Foundation reported, several states are not reporting the numbers of negative test results or pending tests, it's hard to get a complete count of how many people have been tested for coronavirus in the US.
Based on the available data and the population of each country, 1 in 142 South Koreans and 1 in every 786 Americans have been tested for the coronavirus.
Jennifer Horney, founding director of the University of Delaware's epidemiology program, told CNN that epidemiologists generally use rates only like tests per capita to make comparisons.
"I think the important clarification is that we should be considering the number of cases per 1 million population and considering a rate of people tested and not the absolute numbers," Horney said. "The absolute number of tests is not very meaningful."
Until recently, the US was behind South Korea in terms of total tests, despite the fact that the two countries reported their first confirmed cases on the same day. Experts attribute South Korea's recent decline in new coronavirus cases to its early testing efforts, a successful example of what is now commonly referred to as "flattening the curve."