Table 2.
Intraday and Interday Accuracy and Precision of Quality Controls
| Analyte | QC level | Exp Conc (pmol/mL) | Intraday |
Interday |
||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Avg Conc (pmol/mL) | SD | Accuracy (RE, %) | Precision (RSD, %) | Avg Conc (pmol/mL) | SD | Accuracy (RE, %) | Precision (RSD, %) | |||
| AEA | QC1 | 12.50 | 14.07 | 0.47 | 12.5 | 3.4 | 14.17 | 0.38 | 13.4 | 2.7 |
| QC2 | 1.56 | 1.50 | 0.08 | −3.8 | 5.3 | 1.60 | 0.07 | 2.6 | 4.4 | |
| QC3 | 0.39 | 0.35 | 0.01 | −9.7 | 1.5 | 0.38 | 0.04 | −2.6 | 10.5 | |
| QC4 | 0.05 | 0.05 | 0.00 | −4.1 | 7.7 | 0.04 | 0.00 | −9.2 | 9.0 | |
| 2-AG | QC1 | 250.00 | 285.33 | 1.53 | 14.1 | 0.5 | 280.00 | 8.72 | 12.0 | 3.1 |
| QC2 | 31.25 | 34.43 | 0.06 | 10.2 | 0.2 | 33.30 | 1.10 | 6.6 | 3.3 | |
| QC3 | 7.81 | 8.06 | 0.87 | 3.2 | 10.7 | 8.11 | 0.91 | 3.8 | 11.2 | |
| QC4 | 0.98 | 1.09 | 0.07 | 11.2 | 6.5 | 1.09 | 0.08 | 11.2 | 7.0 | |
| OEA | QC1 | 50.00 | 49.70 | 3.14 | −0.6 | 6.3 | 49.07 | 2.86 | −1.9 | 5.8 |
| QC2 | 6.25 | 6.02 | 0.61 | −3.7 | 10.0 | 5.63 | 0.27 | −9.9 | 4.7 | |
| QC3 | 1.56 | 1.39 | 0.03 | −10.9 | 2.1 | 1.37 | 0.06 | −12.2 | 4.1 | |
| QC4 | 0.20 | 0.19 | 0.02 | −2.6 | 8.9 | 0.20 | 0.02 | 2.6 | 11.5 | |
| PEA | QC1 | 50.00 | 43.51 | 3.30 | −13.0 | 7.6 | 44.83 | 2.05 | −10.3 | 4.6 |
| QC2 | 6.25 | 5.43 | 0.17 | −13.1 | 3.2 | 5.34 | 0.25 | −14.6 | 4.6 | |
| QC3 | 1.56 | 1.41 | 0.14 | −9.6 | 9.6 | 1.46 | 0.09 | −6.4 | 6.3 | |
| QC4 | 0.20 | 0.20 | 0.02 | 2.6 | 8.5 | 0.21 | 0.01 | 7.7 | 5.7 | |
| CBD | QC1 | 250.00 | 260.33 | 18.58 | 4.1 | 7.1 | 254.33 | 30.62 | 1.7 | 12.0 |
| QC2 | 31.25 | 28.33 | 1.29 | −9.3 | 4.5 | 27.77 | 1.55 | −11.1 | 5.6 | |
| QC3 | 7.81 | 7.09 | 0.28 | −9.2 | 3.9 | 7.11 | 0.84 | −9.0 | 11.8 | |
| QC4 | 0.98 | 0.94 | 0.08 | −4.1 | 8.1 | 0.95 | 0.05 | −3.1 | 5.3 | |
| Δ9-THC | QC1 | 125.00 | 120.00 | 3.46 | −4.0 | 2.9 | 130.00 | 12.29 | 4.0 | 9.5 |
| QC2 | 31.25 | 27.23 | 2.84 | −12.9 | 10.4 | 29.77 | 0.85 | −4.7 | 2.9 | |
| QC3 | 7.81 | 7.81 | 0.76 | 0.0 | 9.7 | 7.88 | 0.80 | 0.9 | 10.2 | |
| QC4 | 1.95 | 1.82 | 0.36 | −6.7 | 19.7 | 2.19 | 0.18 | 12.3 | 8.0 | |
| Δ9-THC-COOH | QC1 | 750.00 | 759.67 | 109.44 | 1.3 | 14.4 | 848.00 | 106.10 | 13.1 | 12.5 |
| QC2 | 93.75 | 105.33 | 3.51 | 12.4 | 3.3 | 105.00 | 3.46 | 12.0 | 3.3 | |
| QC3 | 23.44 | 22.30 | 2.80 | −4.9 | 12.6 | 25.37 | 0.92 | 8.2 | 3.6 | |
| QC4 | 2.93 | 3.39 | 0.10 | 15.7 | 2.8 | 2.94 | 0.49 | 0.3 | 16.7 | |
Accuracy was reported as percentage RE for the measured mean of spiked QCs against the nominal target value. Precision was calculated as the percentage of RSD from repeated QC measurements.
Avg Conc, average concentration from repeated QC measurements (n=3); Exp Conc, expected concentration; QC, quality control; RE, relative error; RSD, relative standard deviation; SD, standard deviation.