Antigen tests are more likely to be positive on high viral loads than low viral loads. This means that you should have a stronger update towards not-likely-to-infect-others than you should have towards being not-sick. There’s some previous discussion of that here, with the most useful source of data being this paper that looks at contact-tracing data to figure out the likelihood that people who actually went on to infect others would’ve tested positive. The headline result is “The most and least sensitive LFDs would detect 90.5% (95%CI 90.1-90.8%) and 83.7% (83.2-84.1%) of cases with PCR-positive contacts respectively.” I haven’t criticially examined the methodology.
Antigen tests are more likely to be positive on high viral loads than low viral loads. This means that you should have a stronger update towards not-likely-to-infect-others than you should have towards being not-sick. There’s some previous discussion of that here, with the most useful source of data being this paper that looks at contact-tracing data to figure out the likelihood that people who actually went on to infect others would’ve tested positive. The headline result is “The most and least sensitive LFDs would detect 90.5% (95%CI 90.1-90.8%) and 83.7% (83.2-84.1%) of cases with PCR-positive contacts respectively.” I haven’t criticially examined the methodology.