Screening tests are generally conducted on asymptomatic
people with an increased probability of having
or developing a disease, whereas diagnostic testing
is conducted to establish the presence of a disease,
typically in patients who are symptomatic. Previous
screening strategies for HBV and HCV were based on
the identification of such potentially stigmatizing risk
factors as a history of injection drug use or unprotected
sex with multiple partners, which were seldom
assessed by providers or disclosed by patients