In 2020, uninsured adults (including many with chronic diseases) were less likely than the insured to have been tested for COVID-19 despite having higher rates of positive test results.
The Families First Coronavirus Act (revised by the CARES Act) required insurers to cover COVID-19 testing without cost sharing, and provided public payment for testing uninsured individuals. However, it allowed providers not seeking public reimbursement to charge uninsured patients for testing. A secret shopper study found that 84% of urgent care centers charged uninsured individuals for COVID-19 testing.1 Media reports,2 moreover, have suggested that many individuals received large bills for testing despite the regulations. It seems likely that cost concerns deterred some uninsured individuals from seeking testing.
Our finding that the uninsured had a higher unadjusted incidence of positive COVID-19 tests, but not clinician-reported infections, probably reflects disparities in access to clinicians—findings consonant with a trend toward a larger increase in all-cause mortality among the uninsured relative to the insured in 2020.3
Our nationwide analysis extends previous reports of language-,4 race/ethnicity-,5 and socioeconomic-based6 testing disparities in several locales. A limitation of our study is that test results were self-reported. Underdiagnosis of COVID-19 was likely greater among the uninsured, as reflected in higher test positivity. Although we controlled for multiple confounders, observational studies cannot prove causality. Representativeness of NHIS respondents is a potential concern; however, the proportion of our sample with a positive COVID-19 test is similar to the proportion estimated from publicly available CDC case microdata (authors’ unpublished analysis).
The mismatch we observed between testing and COVID-19 risk has important implications. New antiviral medications require prompt diagnosis (and initiation) after symptom onset to be effective; disparities in testing access could impede the equitable use (and efficacy) of such agents. Moreover, the Biden administration’s requirement that insurers cover home rapid antigen tests will not aid the uninsured, potentially widening testing disparities.
Further coverage expansion is needed to achieve more equitable and effective COVID-19 care.