Table 3

Comparison of mean differences between various clinical parameters stratified on below/above-median HBsAg levelsa

Clinical parameterHBsAg levels below medianHBsAg levels above median
No. of samplesdMean differencebLimit of agreement (±2 SD)No. of samplesdMean differencebLimit of agreement (±2 SD)
Overall620.100−0.500, 0.800640.200−0.500, 0.900
HBeAg status
    HBeAg positive130.116−0.384, 0.615560.197−0.591, 0.985
    HBeAg negative490.132−0.553, 0.81780.208−0.044, 0.460
HBV-DNAc
    >2,000 IU/ml540.125−0.550, 0.800210.321−0.799, 1.440
    ≤2,000 IU/ml80.153−0.292, 0.597430.139−0.288, 0.565
HBV genotype
    A150.118−0.205, 0.442440.222−0.634, 1.079
    D30.003−0.268, 0.27340.061−0.095, 0.216
    E40.077−0.215, 0.3693-0.033−0.293, 0.228
    G+A/G90.168−0.310, 0.64760.249−0.248, 0.746
Precore (W28) mutation
    Yes120.087−0.241, 0.415110.136−0.322, 0.595
    No160.117−0.209, 0.443470.222−0.608, 1.051
YMDD mutation
    Yes200.081−0.188, 0.349400.194−0.634, 1.022
    No50.152−0.266, 0.570150.262−0.437, 0.960
s120/s145 mutationsc
    Yes20.0430.034, 0.0524−0.139−0.482, 0.205
    No290.108−0.238, 0.454520.230−0.559, 1.019
HCV-positive serology
    Yes130.158−1.010, 1.32620.170−0.092, 0.431
    No490.121−0.315, 0.557610.200−0.559, 0.958
HDV-positive serology
    Yes60.268−0.660, 1.19630.2190.139, 0.298
    No560.114−0.500, 0.727600.198−0.568, 0.963
CD4+ T cell count
    >500 cells/mm3160.116−0.607, 0.839260.244−0.119, 0.607
    350-500 cells/mm3160.141−0.610, 0.892200.167−0.930, 1.264
    <350 cells/mm3300.129−0.435, 0.693180.167−0.521, 0.856
  • a Bland-Altman analysis stratified on various HBV and HIV cofactors, presented among patients with high or low values of HBsAg quantity. HBsAg levels are given by the Elecsys technique (median = 3.98 log10 Iu/ml).

  • b Difference of Elecsys to Architect.

  • c P values of <0.1 when mean between-assay differences are compared between strata at HBsAg levels above the median.

  • d Total number of samples with available data for each stratum.