Hepatitis B antigen card test III: sensitivity and specificity.

A simple, rapid hepatitis B antigen card test (card test III) with third-generation sensitivity has been developed. This test is a modification of the charcoal-particle agglutination-inhibition procedure. Sera from voluntary blood donors and hospital patients were tested by the new procedure, by the original inhibition technic, by reversed passive hemagglutination, and by radioimmunoassay. This comparison showed that CT III has a specificity equal to that of radioimmunoassay and is almost as sensitive.