Table 8. Age-specific features of probable dengue diagnosis using the WHO 1997 or 2009 classification schemes.

WHO 1997	18–25 (dengue n = 49; OFI n = 553)	26–35 (dengue n = 60; OFI n = 499)	36–45 (dengue n = 60; OFI n = 327)	46–55 (dengue n = 43; OFI n–287)	56+ (dengue n = 38; OFI n = 212)
Sensitivity %	95.9 (86.0–99.5	98.3 (91.1–99.9)	95.0 (86.1–99.0)	95.4 (84.2–99.4)	73.7 (56.9–86.6)
Specificity %	32.0 (28.1–36.1)	29.1 (25.1–33.3)	26.3 (21.6–31.4)	35.2 (29.7–41.0)	44.8 (38.0–51.8)
PPV %	11.1 (8.3–14.5)	14.3 (11.1–18.0)	19.1 (14.8–24.1)	18.1 (13.3–23.7)	19.3 (13.2–26.7)
NPV %	98.9 (96.0–99.9)	99.3 (96.3–99.9)	96.6 (90.5–99.3)	98.0 (93.2–99.8)	90.5 (83.2–95.3)

PPV and NPV denote positive and negative predictive values, respectively.

Values in parentheses are the 95% confidence intervals.