Now testing is opt-out, not opt-in

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Shield test's negativity (or "specificity") rate is 98.9%, according to themselves (slide 4): https://www.iasaedu.org/cms/lib/IL01923163/Centricity/Domain/4/SHIELD%20IL%20IDPH%20overview%20050621.pdf

That means that the test correctly returns a negative result 98.9% of the time when the person is truly negative, and returns a "false positive" 1.1% of the time.

The Washington Post article posted earlier:

"Rapid antigen and saliva PCR tests, which are frequently used in schools, can have a false positive rate of 1 or 2 percent. That may sound low, but statisticians know that, when testing in a setting of low prevalence of disease, even a single-digit false-positive rate can be extremely problematic."

This study uses a slightly less specific test (the BinaxNow rapid test), which has a specificity of 98.5% (https://abbott.mediaroom.com/2020-08-26-Abbotts-Fast-5-15-Minute-Easy-to-Use-COVID-19-Antigen-Test-Receives-FDA-Emergency-Use-Authorization-Mobile-App-Displays-Test-Results-to-Help-Our-Return-to-Daily-Life-Ramping-Production-to-50-Million-Tests-a-Month)


The ASM study shows that with a similar test specificity, and low PREVALENCE rates (0.1% to 1.0%), the percentage of positive tests that are false is between 60 and 94% (it's lower when the prevalence is higher). https://asm.org/Articles/2020/November/SARS-CoV-2-Testing-Sensitivity-Is-Not-the-Whole-St

SO WHAT IS PREVALENCE DURING DELTA?

During delta and with twice weekly testing (so a lot of tests), the UK found a prevalence rate in schools of 0.27% in primary schools and 0.42% in secondary schools in June, 2021. Note that they didn't mask, and don't have vaccination approval for the 12-15 year olds. They did of course do other mitigation measures related to the testing. I offer this as it seems to be one of the only studies of PREVALENCE in schools, during delta, where there was lots of testing. https://www.gov.uk/government/news/covid-19-study-finds-lower-prevalence-in-schools

PREVALENCE outside of schools in the UK during early delta (June 24 to July 12) was 0.63%. (https://www.medicalnewstoday.com/articles/covid-19-in-england-rising-infections-as-delta-variant-takes-hold#Delta-surge).

How does that PREVALENCE compare to covid CASE RATES (which is what we all obsessively look at in DC)? Between June 24 and July 12, UK’s 7-day case rates per 100,000 went from 145 to 358 (https://coronavirus.data.gov.uk/details/cases). In DC terms (of cases per day instead of 7 days) that is about 20/100,000 per day to 51/100,000 per day.

The point being that we likely have low prevalence + Probably even lower in schools as that's been true consistently + test has a specificity greater than 1% = whole lot of false positives.

Sigh. Didn’t even look at this particular test’s specificity plus secondary testing by this lab as a mitigant for false positives. DC has actually entered into a pretty promising relationship here. Wish it was better publicized though.

The particular tests specificity is literally cited above.

Wrong. Shield T3 is greater than 99% and they retest positives. The link to the actual site has been posted numerous times.

Further, we test for three genes present in COVID-19 (vs. one gene for some other tests), with a specificity of 99.8-99.9% and very, very few false positives.
https://www.shieldt3.com/shield-t3/frequently-asked-questions/

I'm PP asking for that, and thank you.

NP. I just want to make sure everyone is looking at the correct data before people write off the test. It seems quite impressive.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Shield test's negativity (or "specificity" rate is 98.9%, according to themselves (slide 4): https://www.iasaedu.org/cms/lib/IL01923163/Centricity/Domain/4/SHIELD%20IL%20IDPH%20overview%20050621.pdf

That means that the test correctly returns a negative result 98.9% of the time when the person is truly negative, and returns a "false positive" 1.1% of the time.

The Washington Post article posted earlier:

"Rapid antigen and saliva PCR tests, which are frequently used in schools, can have a false positive rate of 1 or 2 percent. That may sound low, but statisticians know that, when testing in a setting of low prevalence of disease, even a single-digit false-positive rate can be extremely problematic."

This study uses a slightly less specific test (the BinaxNow rapid test), which has a specificity of 98.5% (https://abbott.mediaroom.com/2020-08-26-Abbotts-Fast-5-15-Minute-Easy-to-Use-COVID-19-Antigen-Test-Receives-FDA-Emergency-Use-Authorization-Mobile-App-Displays-Test-Results-to-Help-Our-Return-to-Daily-Life-Ramping-Production-to-50-Million-Tests-a-Month)


The ASM study shows that with a similar test specificity, and low PREVALENCE rates (0.1% to 1.0%), the percentage of positive tests that are false is between 60 and 94% (it's lower when the prevalence is higher). https://asm.org/Articles/2020/November/SARS-CoV-2-Testing-Sensitivity-Is-Not-the-Whole-St

SO WHAT IS PREVALENCE DURING DELTA?

During delta and with twice weekly testing (so a lot of tests), the UK found a prevalence rate in schools of 0.27% in primary schools and 0.42% in secondary schools in June, 2021. Note that they didn't mask, and don't have vaccination approval for the 12-15 year olds. They did of course do other mitigation measures related to the testing. I offer this as it seems to be one of the only studies of PREVALENCE in schools, during delta, where there was lots of testing. https://www.gov.uk/government/news/covid-19-study-finds-lower-prevalence-in-schools

PREVALENCE outside of schools in the UK during early delta (June 24 to July 12) was 0.63%. (https://www.medicalnewstoday.com/articles/covid-19-in-england-rising-infections-as-delta-variant-takes-hold#Delta-surge).

How does that PREVALENCE compare to covid CASE RATES (which is what we all obsessively look at in DC)? Between June 24 and July 12, UK’s 7-day case rates per 100,000 went from 145 to 358 (https://coronavirus.data.gov.uk/details/cases). In DC terms (of cases per day instead of 7 days) that is about 20/100,000 per day to 51/100,000 per day.

The point being that we likely have low prevalence + Probably even lower in schools as that's been true consistently + test has a specificity greater than 1% = whole lot of false positives.

Sigh. Didn’t even look at this particular test’s specificity plus secondary testing by this lab as a mitigant for false positives. DC has actually entered into a pretty promising relationship here. Wish it was better publicized though.

The particular tests specificity is literally cited above.

Wrong. Shield T3 is greater than 99% and they retest positives. The link to the actual site has been posted numerous times.

Further, we test for three genes present in COVID-19 (vs. one gene for some other tests), with a specificity of 99.8-99.9% and very, very few false positives.
https://www.shieldt3.com/shield-t3/frequently-asked-questions/

I'm PP asking for that, and thank you.

NP. I just want to make sure everyone is looking at the correct data before people write off the test. It seems quite impressive.

It does....but I'm worried about the conflict of the other statement (98.5% ) from the company and what's on the website. Maybe the re-testing is what gets it up to the >99%? I want to hope this isn't just marketing. Would be helpful if there was an FDA approval form, or something that showed some 'verifiable' analysis.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Shield test's negativity (or "specificity" rate is 98.9%, according to themselves (slide 4): https://www.iasaedu.org/cms/lib/IL01923163/Centricity/Domain/4/SHIELD%20IL%20IDPH%20overview%20050621.pdf

That means that the test correctly returns a negative result 98.9% of the time when the person is truly negative, and returns a "false positive" 1.1% of the time.

The Washington Post article posted earlier:

"Rapid antigen and saliva PCR tests, which are frequently used in schools, can have a false positive rate of 1 or 2 percent. That may sound low, but statisticians know that, when testing in a setting of low prevalence of disease, even a single-digit false-positive rate can be extremely problematic."

This study uses a slightly less specific test (the BinaxNow rapid test), which has a specificity of 98.5% (https://abbott.mediaroom.com/2020-08-26-Abbotts-Fast-5-15-Minute-Easy-to-Use-COVID-19-Antigen-Test-Receives-FDA-Emergency-Use-Authorization-Mobile-App-Displays-Test-Results-to-Help-Our-Return-to-Daily-Life-Ramping-Production-to-50-Million-Tests-a-Month)


The ASM study shows that with a similar test specificity, and low PREVALENCE rates (0.1% to 1.0%), the percentage of positive tests that are false is between 60 and 94% (it's lower when the prevalence is higher). https://asm.org/Articles/2020/November/SARS-CoV-2-Testing-Sensitivity-Is-Not-the-Whole-St

SO WHAT IS PREVALENCE DURING DELTA?

During delta and with twice weekly testing (so a lot of tests), the UK found a prevalence rate in schools of 0.27% in primary schools and 0.42% in secondary schools in June, 2021. Note that they didn't mask, and don't have vaccination approval for the 12-15 year olds. They did of course do other mitigation measures related to the testing. I offer this as it seems to be one of the only studies of PREVALENCE in schools, during delta, where there was lots of testing. https://www.gov.uk/government/news/covid-19-study-finds-lower-prevalence-in-schools

PREVALENCE outside of schools in the UK during early delta (June 24 to July 12) was 0.63%. (https://www.medicalnewstoday.com/articles/covid-19-in-england-rising-infections-as-delta-variant-takes-hold#Delta-surge).

How does that PREVALENCE compare to covid CASE RATES (which is what we all obsessively look at in DC)? Between June 24 and July 12, UK’s 7-day case rates per 100,000 went from 145 to 358 (https://coronavirus.data.gov.uk/details/cases). In DC terms (of cases per day instead of 7 days) that is about 20/100,000 per day to 51/100,000 per day.

The point being that we likely have low prevalence + Probably even lower in schools as that's been true consistently + test has a specificity greater than 1% = whole lot of false positives.

Sigh. Didn’t even look at this particular test’s specificity plus secondary testing by this lab as a mitigant for false positives. DC has actually entered into a pretty promising relationship here. Wish it was better publicized though.

The particular tests specificity is literally cited above.

Wrong. Shield T3 is greater than 99% and they retest positives. The link to the actual site has been posted numerous times.

Further, we test for three genes present in COVID-19 (vs. one gene for some other tests), with a specificity of 99.8-99.9% and very, very few false positives.
https://www.shieldt3.com/shield-t3/frequently-asked-questions/

I'm PP asking for that, and thank you.

NP. I just want to make sure everyone is looking at the correct data before people write off the test. It seems quite impressive.

It does....but I'm worried about the conflict of the other statement (98.5% ) from the company and what's on the website. Maybe the re-testing is what gets it up to the >99%? I want to hope this isn't just marketing. Would be helpful if there was an FDA approval form, or something that showed some 'verifiable' analysis.

Yeah I agree. It’s possible that the other figure is from a prior version of the test though.

[Anonymous]

Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

[Anonymous]

Anonymous wrote:Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

Because school doesn't care if your false positive was false. You're still out for 10 days.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

Because school doesn't care if your false positive was false. You're still out for 10 days.

Plus everyone that is a "close contact" of the false positive is out for at least 7 days.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

Because school doesn't care if your false positive was false. You're still out for 10 days.

Plus everyone that is a "close contact" of the false positive is out for at least 7 days.

...if unvaccinated, which is true the < 12s.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

Because school doesn't care if your false positive was false. You're still out for 10 days.

Plus everyone that is a "close contact" of the false positive is out for at least 7 days.

...if unvaccinated, which is true the < 12s.

Right. If DCPS could have a false positive protocol, it would really help.

[Anonymous]

DCPS should describe this testing procedure more clearly, specifically what happens in the case of a positive test. Is anything retested? How frequently do false positives occur (since there are large negative repercussions to those, and they don't actually mitigate covid spread). What happens if your kid tests positive one days through the random asymptomatic testing and the next day tests negative via PCR? What happens to all of the other kids who had to quarantine because of the first kid? How do you establish a false positive?

[Anonymous]

Anonymous wrote:DCPS should describe this testing procedure more clearly, specifically what happens in the case of a positive test. Is anything retested? How frequently do false positives occur (since there are large negative repercussions to those, and they don't actually mitigate covid spread). What happens if your kid tests positive one days through the random asymptomatic testing and the next day tests negative via PCR? What happens to all of the other kids who had to quarantine because of the first kid? How do you establish a false positive?

This would be helpful. Clearly you must treat a positive as positive until there is data to the contrary. But it would be reassuring if they allowed a negative pcr to return the child without symptoms to school.

[Anonymous]

Anonymous wrote:

Anonymous wrote:How do we opt out?

https://osse.dc.gov/page/school-based-covid-19-testing

I'm not seeing to whom you submit. Also - is there a way to electronically submit? It seems like you have to print it out. Thanks.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

Because school doesn't care if your false positive was false. You're still out for 10 days.

Ding, ding, ding! This is why I have opted out for my vaccinated daughter. No testing asymptomatic vaccinated people, please! If she has symptoms I will keep her home and get her tested . . . but not putting her into this DCPS testing quagmire.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:How do we opt out?

https://osse.dc.gov/page/school-based-covid-19-testing

I'm not seeing to whom you submit. Also - is there a way to electronically submit? It seems like you have to print it out. Thanks.

Take a photo and email it to your registrar.

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

Because school doesn't care if your false positive was false. You're still out for 10 days.

Ding, ding, ding! This is why I have opted out for my vaccinated daughter. No testing asymptomatic vaccinated people, please! If she has symptoms I will keep her home and get her tested . . . but not putting her into this DCPS testing quagmire.

One more time: DOH recommends this program for *unvaccinated* students.

They don’t want to test a bunch of asymptomatic, vaccinated people.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Why is everyone so worried about false positives? If you get a positive result, go get a PCR test to confirm. If that's negative, great.

Because school doesn't care if your false positive was false. You're still out for 10 days.

Another reason for those over 12 to be vaccinated. A vaccinated person with a positive rapid test can take a pcr to confirm. If the pcr is negative, they don’t have to quarantine.