Research Article

Analytical and Clinical Comparison of Two Fully Automated Immunoassay Systems for the Diagnosis of Celiac Disease

Table 3

Qualitative agreements between all assays.

Assay % PPA (95% CI)% NPA (95% CI)% TPA (95% CI)kappa (95% CI)

QF versus FEIA tTG IgA (FEIA equiv = positive)98.5 (92.1–100.0)99.3 (96.2–100.0)99.1 (96.6–99.9)0.98 (0.95–1.01)
QF versus FEIA tTG IgA (FEIA equiv = negative)100.0 (93.7–100.0)92.9 (87.7–96.4)94.8 (90.9–97.4)0.88 (0.80–0.95)
QF versus FEIA tTG IgG (FEIA equiv = positive)75.0 (55.1–89.3)96.7 (93.0–98.8)93.9 (89.7–96.7)0.73 (0.59–0.87)
QF versus FEIA tTG IgG (FEIA equiv = negative)80.0 (56.5–94.3)94.3 (90.0–97.1)92.9 (88.6–96.0)0.64 (0.48–0.81)
QF versus FEIA DGP IgA (FEIA equiv = positive)93.0 (80.9–98.5)91.7 (86.5–95.4)92.0 (87.5–95.3)0.77 (0.67–0.88)
QF versus FEIA DGP IgA (FEIA equiv = negative)90.0 (78.2–96.7)94.4 (89.7–97.4)93.4 (89.2–96.3)0.82 (0.73–0.91)
QF versus FEIA DGP IgG (FEIA equiv = positive)98.2 (90.4–100.0)96.2 (91.8–98.6)96.7 (93.3–98.7)0.92 (0.86–0.98)
QF versus FEIA DGP IgG (FEIA equiv = negative)100.0 (92.0–100.0)89.9 (84.3–94.0)92.0 (87.5–95.3)0.79 (0.69–0.88)

Note: PPA: positive percent agreement, NPA: negative percent agreement, TPA: total percent agreement, QF: QUANTA Flash; FEIA: fluoroenzyme immunoassay.