<P> All diagnostic tests have limitations, and sometimes their use may produce erroneous or questionable results . </P> <Ul> <Li> False positive: The test incorrectly indicates that HIV is present in a non-infected person . </Li> <Li> False negative: The test incorrectly indicates that HIV is absent in an infected person . </Li> </Ul> <Li> False positive: The test incorrectly indicates that HIV is present in a non-infected person . </Li> <Li> False negative: The test incorrectly indicates that HIV is absent in an infected person . </Li>

When is the western blot test used in donor testing