Table 3 Clinical agreement and misclassification rates between CD4 measured on EDTA Day 0 (reference test) and CD4 measured on ST Day 7 and Day 14 (index test) at CD4 thresholds for ART eligibility of 350 cells/μL and 500 cells/μL
EDTA Day 0 | ST Day 7 | Sensitivity: 100 (78.2 – 100); PPV: 100 (78.2 – 100) | ||
≤350 | ≤350 | Total | Specificity: 100 (89.7 – 100); NPV: 100 (89.7 – 100) | |
≥350 | 15 | 0 | 15 | Total misclassification rate: 0 |
≥350 | 0 | 34 | 34 | Upward misclassification rate: 0 |
Total | 15 | 34 | 49 | Downward misclassification rate: 0 |
EDTA Day 0 | ST Day 14 | Sensitivity: 83.3 (35.9 – 99.6); PPV: 100 (47.8 – 100) | ||
≤350 | ≥350 | Total | Specificity: 100 (75.3 – 100); NPV: 92.9 (66.1 – 99.8) | |
≤350 | 5 | 1 | 6 | Total misclassification rate: 5.2 |
≥350 | 0 | 13 | 13 | Upward misclassification rate: 5.2 (1/19) |
Total | 5 | 14 | 19 | Downward misclassification rate: 0 |
EDTA Day 0 | ST Day 7 | Sensitivity: 100 (85.2 – 100); PPV: 88.5 (69.8 – 97.6) | ||
≤500 | ≥500 | Total | Specificity: 88.5 (69.8 – 97.6); NPV: 100 (85.2 – 100) | |
≥500 | 23 | 0 | 23 | Total misclassification rate: 6.1 (3/49) |
≤500 | 3 | 23 | 26 | Upward misclassification rate: 0 |
Total | 26 | 23 | 49 | Downward misclassification rate: 6.1 (3/49) |
EDTA Day 0 | ST Day 14 | Sensitivity: 88.9 (51.8 – 99.7); PPV: 80.0 (44.4 – 97.5) | ||
≤500 | ≥500 | Total | Specificity: 80.0 (44.4 – 97.5): NPV: 88.9 (51.8 – 99.7) | |
≥500 | 8 | 1 | 9 | Total misclassification rate: 15.7 (3/19) |
≥500 | 2 | 8 | 10 | Upward misclassification rate: 5.2 (1/19) |
Total | 10 | 9 | 19 | Downward misclassification rate: 10.5 (2/19) |