Table 1.
Absolute and percentage bias of CLEIA relative to EIA, and regression equations estimating the association of EIA-derived concentrations with each bias.
| Bias | Mean | SD | 95% CI | Regression equation |
|---|---|---|---|---|
| Absolute | 8.29 pmol/L | 15.02 pmol/L | 7.48–9.09 pmol/L | Bias = 6.84 pmol/L (95%CI 4.61 to 9.08) + 0.02 (95%CI -0.02 to 0.06) EIA |
| Percentagea | 16.25% | 25.67% | 14.88%–17.62% | Biasb = -2.19% (95%CI -4.01 to -0.36) + 986.83 (95%CI 659.16 to 1314.50) EIA^(-2) + 11442.99 (95%CI 10506.72 to 12379.27) EIA^(-2)*ln(EIA) |
a
Due to very large percentage differences at very low EIA HE4-concentrations, two outliers were excluded (#1; EIA = 1.4, CLEIA = 35.9: #2; EIA = 7.8, CLEIA = 46).
b
Regression equation is from a fractional polynomial regression with exponents (-2, -2).