Table 1.
Discordance Between Rapid Antigen and Follow-Up PCR Tests, by Symptom Status and Time to PCR Test
| PCR within 1 D of Antigen Test |
PCR within 2 D of Antigen Test |
|||||
|---|---|---|---|---|---|---|
| Overall | Symptomatic | Asymptomatic | Overall | Symptomatic | Asymptomatic | |
| Total antigen tests, n | 171,280 | 3052 | 168,228 | 171,280 | 3052 | 168,228 |
| Antigen tests with a follow-up PCR test, n (%) | 14,720 (8.6%) | 623 (20.4%) | 14,097 (8.4%) | 20,991 (12.3%) | 761 (24.9%) | 20,230 (12.0%) |
| Negative antigen tests with positive follow-up PCR test, n | 808 | 58 | 750 | 1324 | 79 | 1245 |
| % of total antigen tests with discordant PCR | 0.5% | 1.9% | 0.4% | 0.8% | 2.6% | 0.7% |
| % of repeated tests with discordant PCR | 5.5% | 9.3% | 5.3% | 6.3% | 10.4% | 6.2% |
| Positive antigen tests with negative follow-up PCR test, n | 312 | 13 | 299 | 337 | 15 | 322 |
| % of total antigen tests with discordant PCR | 0.2% | 0.4% | 0.2% | 0.2% | 0.5% | 0.2% |
| % of repeated tests with discordant PCR | 2.1% | 2.1% | 2.1% | 1.6% | 2.0% | 1.6% |
Symptomatic vs asymptomatic determined based on whether the resident had new onset symptoms in the 5 days prior to testing. Data as of January 10, 2021.