From the coronvirus story in today's Palm Beach Post.
...Still, with the growth in cases slowing, one metric that has stubbornly refused to drop is the percentage of people testing positive.
While the positivity rate has declined in recent days, it is still higher than the 10% sought by state health officials, much less the 5% recommended by the World Health Organization.
In an abrupt reversal on Tuesday, DeSantis broke ranks with health experts, saying he no longer believes the positivity rate is a good way to measure the prevalence of the disease.
His change of heart came after the American Academy of Pediatrics said schools shouldn’t be allowed to reopen unless the positivity rate drops below 5%. DeSantis is an ardent believer that schools should reopen but online classes should be available for parents who don’t want their children to mingle with teachers and classmates.
DeSantis acknowledged that he was once a champion of the positivity rate.
“I was religiously hyping the positivity in March, April, May,” he acknowledged at a press conference Tuesday in Jacksonville. “The problem is the way these test are reported. Some labs don’t report the negatives religiously, some do data dumps.”
“I’d be very cautious of tying a child’s future to the efficacy of some lab dumping positives,” he said.
Top health officials, including the White House Coronavirus Task Force, have said that a 14-day drop in the positivity rate or a 14-day drop in new cases indicate that it is safe to allow businesses and entertainment venues to reopen.
DeSantis cited the positivity rate in May when he lifted restrictions on businesses throughout the state even as the number of cases grew.
Dr. Matt Lambert, an emergency room physician who lives in Washington, D.C., and is chief medical information officer for the HCI Group, said the positivity rate is a key metric decision-makers should use.
“The higher the positivity rate, the more cases you can expect to see in a population,” he said in an statement. “If your goal is to make decisions about schools based on science, the positivity rate is a good marker. However, it is irrelevant if you are making decisions based on economics or politics.”
He predicted that schools will suffer the same fate as Major League Baseball if they reopen. Baseball’s efforts to launch a short season have been plagued with many players and staff, including more than 20 on the Miami Marlins, testing positive for the virus.
(A letter writer today asked, If six women are pregnant, and you test only one of them, does that mean the other five are no longer pregnant?)
Right, my wife has trotted the pregnancy-test metaphor past me, too. It's a good one.
ReplyDeleteI have no idea what your guv is referring to re: "data dumps".
The idea of a positivity rate, as opposed to a raw count of positive test results, is that the sheer number of tests administered can rise or fall from one day to the next. Our somewhat-numerically-challenged prez latched onto that day-to-day variability when he claimed, idiotically, that the key to reducing the spread of the virus is to simply administer fewer tests:* fewer tests, voila! fewer positives. The virus is in retreat!
There is a critical assumption buried in the president's crooked approach: that the number of positives correlates strongly with the number of tests administered. That often is the case, but not always. A couple of months ago in Illinois, our test capacity was ramping up but the number of positives was declining (which is good!). And the opposite also can occur: the number of tests administered can decline, but the number of positives can increase (which is bad!).
Measuring the positivity rate controls for all this variability. If, on a Monday, a state conducts 100,000 tests and the positivity rate is 10%; and then the next day, the state conducts only 50,000 tests and the positivity rate still is 10%; then it's a reasonable conclusion that the virus is spreading at a constant (and high!) rate.
One more comment: the raw number of positives still is an important metric, because it helps assess the likely impact on ICU and respirator capacity. If a state's capacity for ICU beds is 10,000, there is an important difference between 15,000 and 7,500 daily positives. Different metrics can be useful for different purposes. It's helpful to have a governor or a president with a reasonable level of numeracy, although most people don't make their voting decisions based on whether a chief executive can actually look at a page full of numbers and understand them. But even if the chief executive flunked math, he should have people working for him who didn't; he should be willing to listen to them; and he should incorporate their advice appropriately into his decision-making.
* I consider that incredibly stupid comment by the president to be a bit of a window into the soul of an inveterate book-cooker. Once can't help wonder: if Trump's first instinct is to cook the coronavirus books, what other books has he cooked over the course of his long, flamboyant and dodgy business career?
Your last question is one New York DA Cyrus Vance is said to be looking into -- in his early stages, unfortunately. He has the Deutschebank records now, though. That was the last major bank standing that would lend to the alleged billionaire.
DeleteBy data dumps, he means labs that don't announce results every day but put out several days' worth at once. DiSantis seems to think that cooks the positivity trend lines, but when you are consistently way over 10 you can't cook much into or out of your problem. If you go back and test the other five pregnant women, it doesn't mean they just got pregnant. But no matter when you test, after six or seven months you know pretty much where you are.
I hope you noticed he wants the schools to open physically AND provide for distance learning. ISTM (and to teachers I know) that teaching in a classroom and teaching on line are EACH fulltime jobs. But with DeSantis, all things are possible.
A couple of thoughts... Not for the first time, I have thought that politicians could benefit from taking Statistics 101. That is if they really wanted to understand, which is questionable.
DeleteThe second thought is to do with his statement, "I’d be very cautious of tying a child’s future to the efficacy of some lab dumping positives,” As a parent I've observed that kids are pretty resilient. And they want to learn, if given half a chance. How m any of us learned in less than optimal circumstances? We were talking recently about clsssrooms with 40 or more kids taught by religious sisters who didn't have a degree. And my mom's "little house on the prairie" one-room school. Thinking also of the movie "Slumdog Millionaire". I think we need to get beyond the notion that a kid's whole future is going to be determined by a school year of mixed or online classes.
"I hope you noticed he wants the schools to open physically AND provide for distance learning. ISTM (and to teachers I know) that teaching in a classroom and teaching on line are EACH fulltime jobs."
DeleteYep. My kid, who is a Catholic school teacher, apparently is going to be asked to do the same. She said exactly the same thing: it's like doing two jobs at once.
In the business world, I've attended many meetings and workshops that are both on-site (i.e. in a conference room) and remote (i.e. with people dialed in remotely). The remote attendees always are second-class citizens. The on-site attendees start having side conversations among themselves, which the camera and microphone don't pick up. The remote attendees miss a ton. Human communication is pretty complicated, even in a tightly disciplined environment. Technology is helpful but it's not an equalizer.
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DeleteJim, did your daughter feel that online instruction was meeting at least some of the educational goals during the lockdown?
DeleteI think she sees it as a poor substitute. As she teaches a young group (2nd graders), they're not self-sufficient when it comes to showing up on the Zoom meeting: parents or caregivers need to stop whatever they're doing to put the kids online. And it's unnatural for kids that age to learn this way. They want to be in class. She tells us that the Zoom session would reach a point each session, after about 20-25 minutes, where the kids would stop paying attention and start talking to one another. They weren't getting the social interaction with one another on the playground, in the lunchroom and so on, so they were using the Zoom session.
DeleteThere is another aspect to this which doesn't come into play for a public school but is critical to a Catholic school's mission: the spiritual-formation aspect of a Catholic education. For example, the classes aren't able to attend school masses when they're not in school together. In addition, 2nd grade is a big sacramental-prep year: first reconciliations and first communions take place that year. Her class from last year still hasn't made its first communion, because of the virus. This year, depending on whether the school is able to able to stay open and how many parents elect to send their children to the school each day, she's looking at having to do remote sacramental prep for at least part of the class. It should be possible - but it's far from optimal.
Earlier in the summer my husband was talking with the principal of our parish grade school. She expressed concern that they would lose enrollment if they weren't able to open with 5 day, in-person classes. He pointed out that if they weren't able to, the public schools likely couldn't, either. She said, "Yes, but the public school doesn't charge tuition." Making the point that at least for some families it would be a cost vs benefits calculation.
ReplyDeleteYou are right that the spiritual formation aspect is made a lot more difficult when the kids aren't there in person. And the younger kids definitely have a harder time with online learning. My granddaughter who is going into 7th grade has done well with online, she is pretty self motivated. The one going into 3rd grade, and the 1st grader, are another story.
This was in reply to Jim's comment at 11:13 AM.
DeleteI agree with your principal. As it happens, around here the dynamic is sort of the inverse: the public schools are starting in remote-only mode, where as the Catholic schools are starting with five days per week in the classroom. Consequently, some parents who otherwise wouldn't pay the tuition, are enrolling their children in Catholic schools - presumably because the parents need to work and can't closely monitor/manage their children's remote-attendance activities. It's difficult to shake off the suspicion that this financial boon wasn't entirely unforeseen by the Catholic schools.
DeleteAs it turns out the public schools here are going with half and half. The Catholic schools are going with five day. In our school the class sizes run 15-ish. The classrooms seem fairly large, so it is almost a "learning pod" type of arrangement. I hope it works out for both schools, everyone is trying to get through it the best they can.I
DeleteI am more worried about the situation in Omaha, which is a bit of a hot spot right now, and the governor is being an a$$. The granddaughters are in a large parochial school, and our son is a staff member at another school.