Table. 2.
An example of linearity validation
| Level | RC | Measured value | Expected value (E) |
Weight (W) |
Product 1 W∙Y∙E | Product 2 W∙E2 | Predicted value (P) |
Deviation|| | %Deviation |
Within ±ADL?++ | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| #1 | #2 | #3 | #4 | #5 | Mean (Y) |
SD | ||||||||||
| 1 | 1 | 550.1 | 547.7 | 555.4 | 557.6 | 541.1 | 550.38 | 5.84 | 550.38 | 0.1464 | 44,362.03 | 44,362.03 | 536.70 | 13.68 | 2.5 | Yes |
| 2 | 0.9 | 465.2 | 455.1 | 450.6 | 460.1 | 465.5 | 459.30 | 5.78 | 495.34 | 0.1495 | 34,013.66 | 36,682.77 | 483.03 | -23.73 | -4.9 | Yes |
| 3 | 0.75 | 412.5 | 406.3 | 401.1 | 412.3 | 398.5 | 406.14 | 5.70 | 412.79 | 0.1541 | 25,841.06 | 26,263.85 | 402.53 | 3.61 | 0.9 | Yes |
| 4 | 0.6 | 321.2 | 318.1 | 320.0 | 321.1 | 325.6 | 321.20 | 2.47 | 330.23 | 0.8218 | 87,170.64 | 89,620.75 | 322.02 | -0.82 | -0.3 | Yes |
| 5 | 0.5 | 270.1 | 277.6 | 266.1 | 268.1 | 271.2 | 270.62 | 3.90 | 275.19 | 0.3285 | 24,462.58 | 24,875.68 | 268.35 | 2.27 | 0.8 | Yes |
| 6 | 0.4 | 208.1 | 207.5 | 210.1 | 215.5 | 207.8 | 209.80 | 2.99 | 220.15 | 0.5585 | 25,797.53 | 27,070.43 | 214.68 | -4.88 | -2.3 | Yes |
| 7 | 0.25 | 135.8 | 130.1 | 131.1 | 134.5 | 136.9 | 133.68 | 2.65 | 137.60 | 0.7141 | 13,135.35 | 13,520.04 | 134.18 | -0.50 | -0.4 | Yes |
| 8 | 0.15 | 85.1 | 86.3 | 82.3 | 83.5 | 84.1 | 84.26 | 1.36 | 82.56 | 2.6847 | 18,675.51 | 18,298.05 | 80.51 | 3.75 | 4.7 | Yes |
| 9 | 0.08 | 48.5 | 47.6 | 45.5 | 47.5 | 43.0 | 46.42 | 1.97 | 44.03 | 1.2868 | 2,630.08 | 2,494.69 | 42.94 | 3.48 | 8.1 | Yes |
| 10 | 0.05 | 29.0 | 30.1 | 29.9 | 26.2 | 26.5 | 28.34 | 1.67 | 27.52 | 1.7944 | 1,399.46 | 1,358.91 | 26.84 | 1.50 | 5.6 | Yes |
| 11 | 0.03 | 16.5 | 14.5 | 15.0 | 16.6 | 17.1 | 15.94 | 1.01 | 16.51 | 4.9485 | 1,302.41 | 1,349.10 | 16.10 | -0.16 | -1.0 | Yes |
| SUM | >278,790.31 | >285,896.32 | ||||||||||||||
| A |
0.9751 | |||||||||||||||
*Expected value (E): the calculated value using the value of the high-level sample and RC. E=RC∙Y; †W =R/(SD)2; ‡A=(Sum of Product 1)/(Sum of Product 2); §Predicted value (P): the value after applying the weight. P=A∙E; ||Deviation=Y–P; ¶%Deviation=100∙(Deviation)/P; **Mean (Y): mean of measured values for each level; ++If the ADL is 10% in this example, all of %deviation meets the goal.
Abbreviations: RC, relative concentration; SD, standard deviation; ADL, allowable deviation from linearity; R, replicate.
Lab Med Online 2024;14:163~175 https://doi.org/10.47429/lmo.2024.14.3.163
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