From the Document: "The availability of home antigen testing alongside continued challenges in pursuing PCR [polymerase chain reaction] and antigen tests outside of the home means it is likely that some positive cases are not represented in official counts of cases or positivity rates. Community survey methods could prove helpful in evaluating the extent to which such cases may be missing from official COVID-19 [coronavirus disease 2019] tracking statistics. In this brief report, we assess the extent to which positive results on home antigen tests are not reflected in the number of official cases in the United States. In our current survey, we asked individuals if they had tested positive, and then whether they had ever tested positive using an 'at-home' test. [...] In our most recent wave, out of 10,759 respondents:  63% reported ever having been tested for COVID-19.  18% reported ever having tested positive using any type of test.  4% reported testing positive using an at-home test.  31% of individuals who had a positive test at home did not follow up with a test at their doctor's office or a testing facility, and thus are likely not captured in official data.  We estimate that cases have been undercounted by about 6% on average among adults, and likely more so for demographics that use at-home tests more heavily (younger individuals, those with higher income and education, Democrats)."
The COVID States Project Report No. 79
Northeastern University; Harvard Medical School; Rutgers University; Shorenstein Center on Media, Politics, and Public Policy; Northwestern University. Posted here with permission. Document is under a Creative Commons license and requires proper attribution and noncommercial use to be shared: [https://creativecommons.org/licenses/by/4.0/]
The COVID States Project: https://covidstates.org/