2Gall D, Nielsen K.Comparison of some methods for determining cutoff values for serological assays: a retrospective study using the fluorescence polarization assay. J Immunoassay Immunochem, 2001,22:85-98.
3Ridge SE, Vizard AL. Determination of the optimal cutoff value for a serological assay: an example using the Johne′s absorbed EIA. J Clin Microbiol, 1993, 31: 1256-1261.
4Fernando SA, Wilson GS. Studies of the 'hook' effect in the one-step sandwich immunoassay. J Immunol Methods, 1992,15(1-2):47-66.
5Palomaki P. Simultaneous use of poly- and monoclonal antibodies as enzyme tracers in a one-step enzyme immunoassay for the detection of hepatitis B surface antigen. J Immunol Methods, 1991,145:55-63.
6Jongerius JM, Wester M, Cuypers HT, et al. New hepatitis B virus mutant form in a blood donor that is undetectable in several hepatitis B surface antigen screening assays. Transfusion, 1998,38:56-59.
7Weinberger KM, Bauer T, Bohm S, et al. High genetic variability of the group-specific a-determinant of hepatitis B virus surface antigen (HBsAg) and the corresponding fragment of the viral polymerase in chronic virus carriers lacking detectable HBsAg in serum. J Gen Virol, 2000,81(Pt 5):1165-1174.
8Weinberger KM, Zoulek G, Bauer T, et al. A novel deletion mutant of hepatitis B virus surface antigen. J Med Virol, 1999,58:105-110.
9Oon CJ, Chen WN, Goh KT, et al. Molecular characterization of hepatitis B virus surface antigen mutants in Singapore patients with hepatocellular carcinoma and hepatitis B virus carriers negative for HBsAg but positive for anti-HBs and anti-HBc. J Gastroenterol Hepatol, 2002,17 Suppl:S491-496.
10Fukuda R, Ishimura N, Niigaki M, et al. Serologically silent hepatitis B virus coinfection in patients with hepatitis C virus-associated chronic liver disease: clinical and virological significance. J Med Virol,1999,58:201-207.
