Table 3.
Performance of ILI Case Definitions for RSV-ARTI
| RSV-ARTI (n = 36) |
MA-RSV-ARTI (n = 11) |
|
|---|---|---|
| ILIa | ||
| No. (%) | 4 (11) | 1 (9) |
| Sensitivity (95% CI) | 11 (3–26) | 9 (0–41) |
| Specificity (95% CI) | 93 (91–95) | 84 (77–89) |
| LR+ (95% CI) | 1.6 (.6–4.2) | 0.6 (.1–3.7) |
| LR− (95% CI) | 1.0 (.9–1.1) | 1.1 (.9–1.3) |
| PPV (95% CI) | 8 (2–18) | 4 (0–18) |
| NPV (95% CI) | 95 (94–97) | 93 (88–97) |
| AUC | 0.52 | 0.46 |
| Modified ILIa | ||
| No. (%) | 12 (33) | 4 (36) |
| Sensitivity (95% CI) | 33 (19–51) | 36 (11–69) |
| Specificity (95% CI) | 70 (67–74) | 58 (50–66) |
| LR+ (95% CI) | 1.1 (.7–1.8) | 0.9 (.9–1.0) |
| LR− (95% CI) | 1.0 (.8–1.2) | 1.1 (.7–1.8) |
| PPV (95% CI) | 5 (3–9) | 5 (2–13) |
| NPV (95% CI) | 95 (93–97) | 93 (86–97) |
| AUC | 0.52 | 0.47 |
Abbreviations: ARTI, acute respiratory tract infection; AUC, area under the receiver operating characteristic curve; CI, confidence interval; ILI, influenza-like illness; LR−, negative likelihood ratio; LR+, positive likelihood ratio; MA, medically attended; NPV, negative predictive value; PPV, positive predictive value; RSV, respiratory syncytial virus.
aILI includes measured temperature ≥ 38°C while the modified ILI includes also the feeling of being feverish.