Jennifer Beam Dowd wrote in an article for Slate on Friday that the study by IZA Institute of Labor Economics was not to be trusted
An Oxford epidemiologist has backed up South Dakota Governor Kristi Noem in her skepticism of the widely disputed Sturgis study that claimed 266,000 people were infected with COVID-19 from the single motorcycle rally, saying it is full of assumptions that do not stand up.
Jennifer Beam Dowd wrote in an article for Slate on Friday that the study by IZA Institute of Labor Economics was not to be trusted because it relies heavily on comparing the number of COVID cases in the hometowns of people who attended Sturgis, and towns where none of the residents attended, but doesn't take into consideration any other differentiating factors between them.
It also offers no proof or suggested proof of how the disease spread so quickly from people who attended the rally to those who did not, nor does it address that people will have spent different amounts of time in Sturgis before leaving.
Beam Dowd says there is not enough time for that many people to go to the rally, become infected, travel home, infect others and for the results to show up.
Gov. Kristi Noem (pictured) claimed that infection stats showing a motorcycle rally could have caused 250,000 new Covid-19 cases are 'made up'
The 10-day event took place between August 7 and August 14 in the town of Sturgis, which has a native population of just 7,000 people.
If the study was accurate, it would have meant that 20 percent of the 1.4 million new cases of coronavirus reported between August 2 and September 2 came from the rally.
1) It compares COVID-19 numbers between counties that sent people to the rally and counties that didn't, assuming that that is the only difference between them
2) It does not take into account that people will arrived and left the 10-day rally at different times and that they will have spent varying amounts of time there
3) It assumes that people who attended it went straight home to the counties where the COVID-19 numbers were counted when in fact, they may have traveled more and likely did if they were all motorcycle enthusiasts
4) It offers no proof or explanation of how transmission - ie how it spread so fast and quickly
5) There is simply not enough time since the rally ended and between the study's publication for all those people to have become infected, traveled home, passed it on and for all of these infections to have been reported in official numbers - which require tests
'The Sturgis study essentially tries to re-create a randomized experiment by comparing the COVID-19 trends in counties that rally-goers traveled from with counties that apparently don’t have as many motorcycle enthusiasts.
'While this approach may sound sensible, it relies on strong assumptions that rarely hold in the real world. For one thing, there are many other differences between counties full of bike rally fans versus those with none,' she said.
There are more differences between counties, she wrote, than the fact that some sent people to the rally and some didn't, like geographic, social or economic factors.
'The assumption assumes that every county was on a similar trajectory and the only difference was the number of attendees sent to the Sturgis rally.