covid test
TO UNDERSTAND THE ISSUE AT A HIGH LEVEL, TWO SIMPLISTIC EXAMPLES...
EX1: Of 1000 ASYMPTOMATIC...
if rapidTest *sensitivity* is 80%... 20% will have false negatives
assume 1% of pop are positive ( @ 2% - false positives)
if rapidTest *specificity* is 100% all infection-free would test negative)
from the pre-test probability (1%)
10 in 1000 will have it, 990 will not
considering the 80% sensitivity
8 will test positive,
2 will test negative (false negatives)
Of the 990, 100% test negative ( *specificity* is 100%)