Table 1.
Composition of the external quality assurance sample panel and output requested for the different parameters of performance.
| Parameter | Content | Replicates | Output |
|---|---|---|---|
| Sensitivity | Twofold dilution series containing nominal 1.75 to 112 copies of the reference standard | 8 for each dilution (intra-run) | Frequency of positive results |
| Linear range | Tenfold dilution series containing nominal 7 to 70,000 copies of the reference standard | 4 for each dilution (intra-run) | HIV-1 copies/test |
| Intra-run precision | Eightfold dilution series containing nominal 7 to 3,584 copies of the reference standard | 4 for each dilution | HIV-1 copies/test |
| Inter-run precision | Eightfold dilution series containing nominal 7 to 3,584 copies of the reference standard | 5 for each dilution | HIV-1 copies/test |
| Inter-laboratory reproducibility and intra-laboratory precision | 5 reconstructed clinical samples estimated to contain 38,315/23,684, 2,189/1,942, 808/693, 160/162 and 0/0 copies per million cells at the coordinating lab by qPCR/ddPCR | 3 DNA extractions for each sample, each quantified in duplicate in 3 separate runs (inter-run) | HIV-1 copies/million cells |
| Detection of different subtypes | 7 DNA extracts from MOLT-4/CCR5 cells infected with different HIV-1 subtypes estimated to contain 664/1,068 (A), 469/948 (CRF01_AE), 102,494/233,579 (CRF02_AG), 31,305/36,765 (B), 97,343/121,256 (C), 70,599/83,835 (D), 214,738/297,904 (F) copies per 106 cells at the coordinating lab by qPCR/ddPCR | A duplicate for each sample in intra-run | HIV-1 copies/million cells |