Home testing is popular but carries certain assumed risks. A variety of home tests for COVID-19 may be available and these may vary in quality. The possibility of a false-positive or false-negative result needs to be considered.
Factors affecting accuracy of the results from a home test:
(1) intrinsic performance characteristics of the test
(2) state of any infection at the time of testing (incubating, active, recuperation)
(3) changes to the test during shipping and handling
(4) expiration date of the test
(5) storage by the end-user
(6) compliance with reading the test
(7) interpretation
Performance of the testing:
(1) is affected by the prevalence of the infection (with impact on pre-test probability)
(2) tends to be better when the test is repeated as a series
(3) may be affected by whether the person is symptomatic or not
Consequences of a false-positive result:
(1) unnecessary treatment
(2) unnecessary quarantine, with loss of income and restrictions on services
(3) distraction from other health conditions, with delay in treatment
(4) activation of public health restrictions
(5) social isolation. especially for the elderly
(6) contribute to misinformation about vaccinations
Consequences of a false-negative result:
(1) contact with others while infectious
(2) underestimation of the prevalence of the infection
Ideally results of rapid testing should be confirmed by a high sensitivity, high specificity assay, which could have been done in the first place.
