Table 2.
Inter- and Intra-assay variation of C1-INH complex assays.
| C1s/C1-INH complex | sample 1 | sample 2 | sample 3 | sample 4 | |
|---|---|---|---|---|---|
| Intra-assay variation | |||||
| Operator 1 | mean aliquot 1-3 (ng/mL) | 1161 | 1967 | 1595 | 1285 |
| SD (ng/mL) | 90 | 121 | 49 | 63 | |
| CV (%) | 7.8 | 6.2 | 3.1 | 4.9 | |
| Operator 2 | mean aliquot 1-3 (ng/mL) | 1245 | 2135 | 1868 | 1399 |
| SD (ng/mL) | 47 | 166 | 99 | 43 | |
| CV (%) | 3.8 | 7.8 | 5.3 | 3.1 | |
| Inter-assay variation | |||||
| mean Operator 1 and 2 (ng/mL) | 1203 | 2051 | 1731 | 1342 | |
| SD (ng/mL) | 79 | 159 | 165 | 79 | |
| CV (%) | 6.6 | 7.8 | 9.5 | 5.9 | |
| MASP-1/C1-INH complex | sample 1 | sample 2 | sample 3 | sample 4 | |
| Intra-assay variation | |||||
| Operator 1 | mean aliquot 1-3 (ng/mL) | 273.2 | 115.5 | 57.3 | 35.5 |
| SD (ng/mL) | 6.6 | 0.7 | 3.6 | 0.5 | |
| CV (%) | 2.4 | 0.6 | 6.2 | 1.5 | |
| Operator 2 | mean aliquot 1-3 (ng/mL) | 259.0 | 108.3 | 52.4 | 34.7 |
| SD (ng/mL) | 8.1 | 2.4 | 1.2 | 0.6 | |
| CV (%) | 3.1 | 2.2 | 2.4 | 1.8 | |
| Inter-assay variation | |||||
| mean Operator 1 and 2 (ng/mL) | 266.1 | 111.9 | 54.9 | 35.1 | |
| SD (ng/mL) | 10.2 | 4.3 | 3.6 | 0.7 | |
| CV (%) | 3.8 | 3.8 | 6.6 | 1.9 | |
Intra-assay variation (multiple determinations of single samples within a single test run) and inter-assay variation (multiple determinations of single samples in several assay runs) was determined for both complex assays by calculation of mean concentrations and %CV using 3 independent aliquots of 4 different samples in 2 test runs (performed by 2 different operators). A %CV ≤10 indicates low variation for the intra-assay variation, while a CV% ≤20 indicates low inter-assay variation. %CV, coefficient of variation.