On coronavirus, Trump insists the U.S. has the world's 'No. 1 low mortality rate.' He's wrong — and it's the wrong way to measure success.

On Tuesday afternoon, President Trump returned to the White House briefing room for his first coronavirus press conference in more than two months. Largely resisting the tangential, pugnacious approach he favored during his earlier appearances at the podium, Trump tried instead to rely on data to persuade the American people that his administration is “doing a good job,” in his words, combating COVID-19.

“We’ll be putting up charts behind me showing different statistics — different rates of success,” the president announced early on.

The problem with Trump’s new strategy, however, is that his prized data point is a mirage — an illusion that dissolves under closer inspection, revealing the opposite of the “success” it’s supposed to show.

At the top of his briefing, Trump unveiled a chart labeled “Case Fatality Rate” in big, bold letters. Each color-coded bar corresponded to a particular country or region. The largest bar belonged to France (17.1 percent), followed by the United Kingdom (15.3 percent), Belgium (15.3 percent), Italy (14.3 percent), Spain (10.7 percent), the European Union (10.2 percent), Canada (8 percent), Europe (7.5 percent), Sweden (7.2 percent), Germany (4.5 percent), the world as a whole (4.2 percent) — and then, at the very bottom, the United States (3.7 percent).

“Our case fatality rate has continued to decline and is lower than the European Union and almost everywhere else in the world,” Trump said. “If you watch American television, you’d think the United States was the only country involved with and suffering from the China virus. Well, the world is suffering very badly. ... We’ve done much better than most. And with the fatality rate lower than most, it’s something we can talk about.”

This isn’t the first time Trump has claimed, in effect, that the U.S. is better than any other country at preventing COVID-19 patients from succumbing to the disease. “We have the lowest mortality or just about the lowest mortality in the world,” Trump said last week.

In his Fox News interview with Chris Wallace, broadcast Sunday, the president repeated this assertion, boasting that the U.S. has the world’s “No. 1 low mortality rate.”

Trump is wrong in two ways. For one thing, he seems to be confusing two different metrics: mortality rate and case fatality rate.

He’s also emphasizing the latter (which is basically useless in country-to-country comparisons) over the former (which is actually meaningful).

President Donald Trump speaks during a news conference at the White House, Tuesday, July 21, 2020, in Washington. (Evan Vucci/AP)
President Trump at a news conference at the White House on Tuesday. (Evan Vucci/AP)

Let’s start with the “mortality rate.” This is a per capita measure of how many residents of a particular country or region have died of the disease. Think of it as “COVID-19 deaths per hundred thousand” (or million, or any other convenient number).

For weeks, Trump was saying America’s mortality rate is the lowest in the world. It’s not. According to John Hopkins University, it’s actually the 10th highest, after San Marino, Belgium, the U.K., Andorra, Spain, Italy, Sweden, Chile and France. To date, the U.S. has suffered 43.07 deaths per 100,000 residents. Brazil has suffered 38.25. Mexico has suffered 31.29. Iran has suffered 17.61. Germany has suffered 10.97.

And this actually understates America’s current mortality problem. The mortality rate is typically presented as a cumulative number — that is, how many per capita COVID-19 deaths have occurred so far during the entire pandemic. But you can also measure it daily, which gives you a better sense of how your country is performing right now.

Here, the U.S. is faring even worse. In early April, far more people were dying of COVID-19 per capita across Europe than across the U.S. Today, America’s daily mortality rate is 10 times as high as the European Union’s.

To assist Trump with his briefing, someone in the White House seems to have told him to stop touting America’s (relatively unflattering) COVID-19 mortality rate and start touting its (ostensibly more flattering) case fatality rate instead, which is really what Trump was trying to do all along. Hence the big “Case Fatality Rate” chart.

It didn’t really help him make his point.

The case fatality rate (CFR) of COVID-19 is just the ratio between confirmed COVID-19 deaths and confirmed COVID-19 cases. This sounds like a solid metric, but there’s a hitch. COVID-19 deaths are fairly straightforward to count. But the raw number of COVID-19 “cases” a country finds is totally dependent on how many infections it’s able to detect through testing.

In the midst of a pandemic, this makes CFR a terrible measure of the lethality of a disease — and an even worse way of comparing how well various countries are doing keeping COVID-19 patients alive.

Trump is right that fewer Americans are dying of COVID-19 now than in the spring. He’s also right that this reflects the fact that increased testing is turning up more younger, milder cases, and that treatments have improved.

But that’s not really the story that America’s relatively low CFR tells. The story that it tells is that the U.S. is uncovering a lot more infection than anywhere else.

Think of it this way. To calculate CFR, you take the number of people who have died, and you divide it by the total number of people diagnosed with the disease. So if 10 people have died, and 100 people have been diagnosed with the disease, the CFR is 10 divided by 100, or 10 percent.

The more cases in the denominator, the lower the CFR. This means a country like the U.S. (which has conducted nearly 46 million tests and found more than 3.9 million cases) is almost certain to have a lower CFR than a country like the U.K (which has conducted 8 million tests and found roughly 300,000 cases). It also means the CFR will continue to go down in the country where the virus is continuing to spread and where tests are continuing to come back positive (the U.S.), while remaining higher in the country that has its outbreak under control (the U.K.).

At least until COVID-19 deaths start to catch up with cases, which they tend to do. Right now, the U.S. is averaging 757 coronavirus deaths per day. The E.U. is averaging 96.

Ultimately, this dynamic creates an irksome paradox for Trump. On the one hand, he has repeatedly complained about the number of tests conducted in the U.S., saying it makes the administration look bad — “If we stop testing right now, we’d have very few cases, if any.” On the other hand, America’s increase in testing — and the world-leading number of cases all those tests have turned up — is the main factor that enabled him to brag about the country’s 3.7 percent CFR at Tuesday’s White House briefing.

So perhaps the president should be careful what he wishes for. If, for instance, he gets his way and blocks new money for testing in Congress’s upcoming coronavirus relief package, he’ll probably have to find a new favorite chart.


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