Bulletin of the World Health Organization

Sensitivity and specificity of typhoid fever rapid antibody tests for laboratory diagnosis at two sub-Saharan African sites

Karen H Keddy, Arvinda Sooka, Maupi E Letsoalo, Greta Hoyland, Claire Lise Chaignat, Anne B Morrissey & John A Crump

Volume 89, Number 9, September 2011, 640-647

Table 2. Sensitivity, specificity and predictive values of four rapid diagnostic tests for typhoid fever as determined by comparison with blood culture results

Kit Sensitivity
% (95% CI)
Specificity
% (95% CI)
PPV
% (95% CI)
NPV
% (95% CI)
Cromotest® O : semiquantitative slide agglutination 95.2 (86.5–99.0) 3.6 (0.1–18.3) 25.0 (0.6–80.6) 68.6 (57.7–78.2)
Cromotest® H : semiquantitative slide agglutination 80.3 (68.2–89.4) 50.0 (30.6–69.4) 53.8 (33.4–73.4) 77.8 (65.5–87.3)
Cromotest® O: single tube Widal 87.3 (76.5–94.4) 6.9 (0.8–22.8) 20.0 (2.5–55.6) 67.1 (55.8–77.1)
Cromotest® H: single tube Widal 95.2 (86.5–99.0) 13.8 (3.9–31.7) 57.1 (18.4–90.1) 70.2 (59.3–79.7)
TUBEX® 73.0 (60.3–83.4) 69.0 (49.2–84.7) 54.1 (36.9–70.5) 83.6 (71.2–92.2)
Typhidot® IgM 75.0 (61.1–86.0) 60.7 (40.6–78.5) 56.7 (37.4–74.5) 78.0 (64.0–88.5)
Typhidot® IgG 69.2 (54.9–81.3) 70.4 (49.8–86.2) 54.3 (36.6–71.2) 81.8 (67.3–91.8)

CI, confidence interval; NPV, negative predictive value; PPV, positive predictive value.