Table 3.
Imprecision of the candidate reference measurement procedure for quantitation of serum concentrations of 25(OH)D2 and 25(OH)D3 in five internal quality control materialsa
| Concentration, nmol/L | CV, %
|
||
|---|---|---|---|
| Within-day | Between-day | Total | |
| 25(OH)D2 | |||
| 3.00 | 1.6 | 2.8 | 3.1 |
| 3.08 | 3.8 | 3.7 | 4.9 |
| 4.66 | 3.4 | 3.0 | 4.1 |
| 9.90 | 1.5 | 2.9 | 3.1 |
| 14.8 | 1.7 | 2.1 | 2.5 |
| 25(OH)D3 | |||
| 23.8 | 2.3 | 1.2 | 2.2 |
| 40.6 | 3.1 | 1.0 | 2.7 |
| 49.2 | 0.6 | 1.5 | 1.6 |
| 65.3 | 1.8 | 0.8 | 1.7 |
| 84.5 | 1.5 | 2.0 | 1.8 |
a
Duplicate samples of internal quality control serum were tested in five independent measurement series. The within-day, between-day imprecision, and total CV were calculated for each material using CLSI EP-10-A3 document as a guide [24].