TABLE 1

Comparative performance of iC-GPC Assay with Verigene method and resolution of discordant test results following PCR/sequencing arbitration testing

Assay target (n = 1,081)Sample type% agreement, no. of samples/total no. (95% CI [%])aResolution of iC-GPC Assay discordant results after arbitration testing (no./total no.)a,b
PositiveNegativeFNFPTNTP
Bacterial identification
    S. aureusOverall97.0, 258/266 (94.2–98.5)99.8, 813/815 (99.1–99.9)821/81/2c
Prospective97.0, 258/266 (94.2–98.5)99.7, 645/647 (98.9–99.9)821/81/2c
SimulatedNA, 0/0 (NA)100, 168/168 (97.8–100)00NANA
    S. epidermidisOverall98.3, 231/235 (95.7–99.3)98.3, 832/846 (97.2–99.0)4141/49/14
Prospective98.3, 231/235 (95.7–99.3)97.9, 664/678 (96.6–98.8)4141/49/14
SimulatedNA, 0/0 (NA)100, 168/168 (97.8–100)00NANA
    S. pneumoniaeOverall93.7, 59/63 (84.8–97.5)99.9, 1,017/1,018 (99.5–100)414/41/1
Prospective85.2, 23/27 (67.5–94.1)99.9, 885/886 (99.4–100)414/41/1
Simulated100, 36/36 (90.4–100)100, 132/132 (97.2–100)00NANA
    E. faecalisOverall98.7, 149/151 (95.3–99.6)99.9, 929/930 (99.4–100)211/20/1
Prospective96.7, 59/61 (88.8–99.1)99.9, 851/852 (99.4–100)211/20/1
Simulated100, 90/90 (95.9–100)100, 78/78 (95.3–100)00NANA
    E. faeciumOverall98.6, 70/71 (92.4–99.8)99.8, 1,008/1,010 (99.3–100)120/11/2
Prospective96.6, 28/29 (82.8–99.4)99.8, 882/884 (99.2–99.9)120/11/2
Simulated100, 42/42 (91.6–100)100, 126/126 (97.0–100)00NANA
Resistance determinant
    mecAOverall96.1, 274/285 (93.2–97.8)95.2, 216/227 (91.5–97.3)11111/118/11
Prospective96.1, 274/285 (93.2–97.8)95.2, 216/227 (91.5–97.3)11111/118/11
SimulatedNA, 0/0 (NA)NA, 0/0 (NA)00NANA
    vanAOverall98.3, 59/60 (91.1–99.7)96.9, 158/163 (93.0–98.7)150/12/5
Prospective95, 19/20 (76.4–99.1)93.0, 66/71 (84.6–97.0)150/12/5
Simulated100, 40/40 (91.2–100)100, 92/92 (96.0–100)00NANA
    vanBOverall100, 58/58 (93.8–100)99.4, 163/164 (96.6–100)01NA1/1
Prospective100, 2/2 (34.2–100)98.8, 87/88 (93.8–99.8)01NA1/1
Simulated100, 56/56 (93.6–100)100, 76/76 (95.2–100)00NANA
  • a NA, not applicable; 95% CI, 95% confidence interval.

  • b FN, false negative; FP, false positive; TN, true negative; TP, true positive.

  • c One specimen not available for arbitration testing.