Table 6. Sensitivity, specificity, and area under curve value of the case definitions tested for detection of influenza, stratified by age group and influenza (sub)-type, GROG study, France, 2009–2014 .
| Stratification variable | ECDC ILI | WHO | CDC | |
|---|---|---|---|---|
| Sensitivity % (95% CI) | ||||
| Age group | 0–4 years | 93.4 (92.1–94.5) | 84.2 (82.3–85.9) | 93.3 (91.9–94.4) |
| 05–14 years | 95.8 (94.8–96.7) | 89.8 (88.4–91.1) | 95.4 (94.4–96.3) | |
| 15–64 years | 98.2 (97.5–98.7) | 93.7 (92.6–94.7) | 97.7 (97.0–98.3) | |
| ≥ 65 years | 98.5 (95.7–99.7) | 96.0 (92.3–98.3) | 98.0 (95.0–99.5) | |
| Influenza type | A(H1N1) pdm09 | 96.9 (96.2–97.5) | 91.8 (90.7–92.8) | 96.7 (95.9–97.3) |
| A(H3N2) | 95.6 (94.4–96.5) | 89.2 (87.6–90.7) | 95.0 (93.8–96.1) | |
| B | 94.9 (93.6–96.0) | 86.6 (84.7–88.3) | 94.6 (93.2–95.7) | |
| Epidemic Period | RSV bronchiolitis | 96.7 (95.8–97.4) | 90.1 (88.8–91.3) | 96.1 (95.2–96.9) |
| Influenza pandemica | 97.5 (96.5–98.2) | 92.5 (91.0–93.8) | 97.2 (96.2–97.9) | |
| Influenza seasonalb | 95.5 (94.8–96.2) | 88.9 (87.8–89.9) | 95.2 (94.4–95.9) | |
| Specificity % (95% CI) | ||||
| Age group | 0–4 years | 7.7 (6.9–8.7) | 21.0 (19.7–22.3) | 8.0 (7.2–8.9) |
| 05–14 years | 8.5 (7.2–10.0) | 27.1 (25.0–29.3) | 9.0 (7.7–10.5) | |
| 15–64 years | 4.3 (3.7–5.1) | 19.9 (18.5–21.3) | 5.7 (7.7–10.5) | |
| ≥ 65 years | 4.8 (2.9–7.8) | 13.9 (10.5–18.0) | 6.5 (4.3–9.8) | |
| Influenza type | A(H1N1) pdm09 | 6.6 (6.1–7.1) | 21.4 (20.6–22.3) | 7.3 (6.8–7.9) |
| A(H3N2) | 6.6 (6.1–7.1) | 21.4 (20.6–22.3) | 7.3 (6.8–7.9) | |
| B | 6.6 (6.1–7.1) | 21.4 (20.6–22.3) | 7.3 (6.8–7.9) | |
| Epidemic period | RSV bronchiolitis | 6.6 (5.9–7.5) | 19.3 (18.1–20.5) | 7.6 (6.8–8.4) |
| Influenza pandemica | 6.1 (5.2–7.1) | 18.2 (16.8–19.7) | 7.0 (6.1–8.1) | |
| Influenza seasonalb | 7.0 (6.2–8.0) | 21.3 (19.8–22.8) | 7.8 (6.8–8.8) | |
| AUC % (95% CI) | ||||
| Age group | 0–4 years | 0.506 (0.489–0.522) | 0.526 (0.509–0.542) | 0.507 (0.490–0.523) |
| 05–14 years | 0.522 (0.503–0.541) | 0.585 (0.566–0.604) | 0.522 (0.503–0.541) | |
| 15–64 years | 0.512 (0.497–0.528) | 0.568 (0.553–0.583) | 0.517 (0.501–0.533) | |
| ≥ 65 years | 0.517 (0.467–0.566) | 0.549 (0.501–0.598) | 0.523 (0.473–0.572) | |
| Influenza type | A(H1N1) pdm09 | 0.517 (0.505–0.529) | 0.566 (0.555–0.578) | 0.520 (0.508–0.532) |
| A(H3N2) | 0.517 (0.495–0.526) | 0.553 (0.539–0.568) | 0.512 (0.496–0.527) | |
| B | 0.507 (0.491–0.523) | 0.540 (0.525–0.555) | 0.509 (0.493–0.525) | |
| Epidemic period | RSV bronchiolitis | 0.517 (0.502–0.531) | 0.547 (0.532–0.561) | 0.518 (0.504–0.533) |
| Influenza pandemica | 0.518 (0.500–0.536) | 0.553 (0.536–0.571) | 0.521 (0.503–0.539) | |
| Influenza seasonalb | 0.513 (0.499–0.527) | 0.551 (0.537–0.565) | 0.515 (0.501–0.529) | |
AUC: area under curve; CDC: Centers for Disease Control and Prevention; CI: confidence interval; ECDC: European Centre for Disease Prevention and Control; GROG: Groupes Régionaux d’Observation de la Grippe; ILI: influenza-like illness; RSV: respiratory syncytial virus; WHO: World Health Organization.
a Influenza A(H1N1)pdm09 sample during the 2009 influenza pandemic.
b Influenza A(H1N1)pdm09 and A(H3N2) sample during seasonal influenza epidemics (2010/11, 2011/12, 2012/13, 2013/14).