Table 3 Sensitivity, specificity, PPV, NPV, and overall accuracy of Ada and Rheport for the diagnosis of inflammatory rheumatic diseases including 95% confidence intervals

Total sample (n = 164)

Sensitivity (%)

53.7 (39.7–67.2)

42.6 (29.5–56.7)

53.7 (39.7–67.2)

Specificity (%)

51.8 (42.1–61.4)

63.6 (53.9–72.4)

54.5 (44.8–64.0)

PPV (%)

35.4 (25.3–46.8)

36.5 (25.0–49.6)

36.7 (26.4–48.4)

NPV (%)

69.5 (58.2–78.9)

69.3 (59.2–77.9)

70.6 (59.6–79.7)

Accuracy (%)

52.4 (44.5–60.2)

56.7 (48.8–64.3)

54.3 (46.3–62.0)

Ada first (n = 164)

Sensitivity (%)

56.0 (35.3–75.0)

40.0 (21.8–61.1)

60.0 (38.9–78.2)

Specificity (%)

52.6 (39.1–65.8)

61.4 (47.6–73.7)

54.4 (40.8–67.4)

PPV (%)

34.1 (20.6–50.7)

31.2 (16.7–50.1)

36.6 (22.6–53.1)

NPV (%)

73.2 (56.8–85.2)

70.0 (55.2–81.7)

75.6 (59.4–87.1)

Accuracy (%)

53.7 (42.4–64.6)

54.9 (43.5–65.8)

56.1 (44.7–66.9)

Rheport first (n = 164)

Sensitivity (%)

51.7 (32.9–70.1)

44.8 (27.0–64.0)

48.3 (29.9–67.1)

Specificity (%)

50.9 (37.0–64.7)

66.0 (51.6–78.1)

54.7 (40.6–68.2)

PPV (%)

36.6 (22.6–53.1)

41.9 (25.1–60.7)

36.8 (22.3–54.0)

NPV (%)

65.9 (49.3–79.4)

68.6 (54.0–80.5)

65.9 (50.0–79.1)

Accuracy (%)

51.2 (40.0–62.3)

58.5 (47.1–69.1)

52.4 (41.2–63.5)