[Farm93]

Assuming that NYC's test has accuracy similar to the Stanford test, false positives should not be a major issue for the NYC and NYC-area results.  It could matter for the statewide results.

But we'll need more information to know how good the sampling was.  I saw that they sampled at grocery store and big box store parking lots.  That's potentially more random than calling people or facebook ads, but the devil is always in the details.

For future studies like this, I think one way around the self-selection problem would be to pay people to participate.  If you give everyone an incentive to give blood, maybe you can reduce motivation to get tested as a factor.  I bet China could do a great study--just have the blood extraction people show up at everyone's door with a few police officers.  100% participation guaranteed!

Governor Cuomo explained the methodology and many of the limitations, and didn't oversell the results.   He also stressed some of the groups he hopes to analyze in greater detail in the next few weeks.

I watch the NY briefings and just wish the Federal ones had a similar format.

Today's new wrinkle was the sampling of New Yorkers for antibodies.
21% of NYC participants had antibodies.
Just less than 4% of the upstate residents had antibodies.

NYC probably is the upper bound rate for antibodies nationally.
Upstate NY has had the same stay at home restrictions as NYC, so at this point upstate NY could be close to the rate in many mid-sized states.

I would imagine that Los Angeles is probably in the low teens today, while most of the rest of the CA might be down in the 3-5% range.   I need to imagine and guess because for some inexplicable reason the federal government has yet to do anything like this NY effort nationally.

Using a ~3% rate nationally would imply ~10 million have antibodies and the fatality rate would 0.5% WITH the vast majority of the USA working diligently to slow the infection rate. 

The NY data really makes me want to get an antibody test.   In early March for the first time in years I had a fever and other flu-like symptoms, for 2 days, after spending an evening in a meeting next to someone that had a persistent cough for weeks after visiting China in December.   At the time I was so worried he had COVID19.   Now I almost hope he did have COVID19.

[Farm93]

Assuming that NYC's test has accuracy similar to the Stanford test, false positives should not be a major issue for the NYC and NYC-area results.  It could matter for the statewide results.

But we'll need more information to know how good the sampling was.  I saw that they sampled at grocery store and big box store parking lots.  That's potentially more random than calling people or facebook ads, but the devil is always in the details.

For future studies like this, I think one way around the self-selection problem would be to pay people to participate.  If you give everyone an incentive to give blood, maybe you can reduce motivation to get tested as a factor.  I bet China could do a great study--just have the blood extraction people show up at everyone's door with a few police officers.  100% participation guaranteed!

Governor Cuomo explained the methodology and many of the limitations, and didn't oversell the results.   He also stressed some of the groups he hopes to analyze in greater detail in the next few weeks.

I watch the NY briefings and just wish the Federal ones had a similar format.

Today's new wrinkle was the sampling of New Yorkers for antibodies.
21% of NYC participants had antibodies.
Just less than 4% of the upstate residents had antibodies.

NYC probably is the upper bound rate for antibodies nationally.
Upstate NY has had the same stay at home restrictions as NYC, so at this point upstate NY could be close to the rate in many mid-sized states.

I would imagine that Los Angeles is probably in the low teens today, while most of the rest of the CA might be down in the 3-5% range.   I need to imagine and guess because for some inexplicable reason the federal government has yet to do anything like this NY effort nationally.

Using a ~3% rate nationally would imply ~10 million have antibodies and the fatality rate would 0.5% WITH the vast majority of the USA working diligently to slow the infection rate. 

The NY data really makes me want to get an antibody test.   In early March for the first time in years I had a fever and other flu-like symptoms, for 2 days, after spending an evening in a meeting next to someone that had a persistent cough for weeks after visiting China in December.   At the time I was so worried he had COVID19.   Now I almost hope he did have COVID19.