Table 2.
Regression analysis and mean bias to the reference method using single donor sera.
| LabID# | Intercept (95% CI) | Slope_X (95% CI) | Slope_X2 (95% CI) | Mean percent bias (95% CI)% | Median imprecisiona (min–max)%CV | Number of results reported on samples with target values outside the reportable range |
|---|---|---|---|---|---|---|
| 1 | 16.69 (10.00–23.39) | 0.8062 (0.6996–0.9128) | 37.5 (17.6–57.5) | 6 (3–15) | 55 | |
| 2 | 5.11 (2.99–7.23) | 0.9446 (0.8574–1.0318) | 0.00099 (0.00047–0.0015) | 30.5 (15.6–45.4) | 5 (1–21) | 17 |
| 3 | 3.58 (0.63–6.53) | 0.9327 (0.869–0.9964) | 15.9 (0.1–31.7) | 7 (2–15) | 8 | |
| 4 | −3.48 (−7.60–0.65) | 1.123 (1.0407–1.2053) | 2.65 (−4.66–9.96) | 8 (2–21) | 3 | |
| 5 | 3.76 (2.06–5.47) | 0.9855 (0.9545–1.0165) | 21.4 (11.9–30.9) | 7 (1–18) | 13 | |
| 6 | 7.01 (5.37–8.65) | 0.6137 (0.5672–0.6602) | 10.1 (−12.2–32.4) | 6 (2–14) | 30 | |
| 7 | 14.23 (10.13–18.33) | 0.6297 (0.4662–0.7932) | 0.00189 (0.00086–0.00291) | 27.5 (8.5–46.4) | 13 (5–27) | 19 |
| 8 | 17.7 (14.60–20.80) | 0.8378 (0.6884–0.9873) | 0.00137 (0.00033–0.0024) | 111 (59.3–163) | 15 (6–29) | 58 |
| 9 | 15.29 (9.61–20.96) | 2.2362 (2.0614–2.4111) | 235 (181–289) | 9 (4–21) | 21 | |
| 10 | 16.1 (10.74–21.47) | 2.1687 (2.0221–2.3153) | 230 (178–283) | 16 (4–30) | 21 | |
| 11 | 5.07 (1.95–8.19) | 0.932 (0.8315–1.0325) | 0.00093 (0.00042–0.00145) | 14.7 (9.88–19.6) | 5 (1–13) | 24 |
| 12 | 2.58 (1.21–3.94) | 0.9926 (0.9559–1.0293) | 22.5 (4.19–40.8) | 8 (3–41) | 0 | |
| 13 | 1.23 (0.42–2.04) | 1.0514 (1.02–1.0828) | 12.4 (8.77–15.9) | 7 (4–17) | 0 | |
| 14 | 0.44 (−0.08–0.96) | 0.9400 (0.9205–0.9595) | −2.41 (−5.38–0.56) | 6 (2–57) | 0 | |
| 15 | 0.11 (−0.56–0.78) | 1.0957 (1.0776–1.1139) | 9.79 (7.93–11.66) | 5 (2–12) | 6 | |
| 16 | −0.45 (−0.95–0.04) | 1.1083 (1.0904–1.1262) | 8.31 (6.50–10.13) | 3 (1–21) | 0 | |
| 17 | −0.12 (−2.37–2.14) | 1.1599 (1.1053–1.2144) | 16.39 (10.84–21.94) | 14 (7–75) | 1 |
a
Determined for each sample from duplicate measurements on three days (n = 6).