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Table 1 Clinical performance of POC PCR, laboratory PCR, bacterial culture, and POC RADT when compared with final results by sequencing for group A Streptococcus (n = 255)

From: Diagnosis and antibiotic treatment of group a streptococcal pharyngitis in children in a primary care setting: impact of point-of-care polymerase chain reaction

  Cobas Liat POC PCRa Quidel QuickVue POC RADT Bacterial culture
Final resultb Positive Negative Total Positive Negative Total Positive Negative Total
Positive 105 1 106 94 9 103 79 0 79
Negative 5 144 149 16 136 152 31 144 175
Total 110 145 255 110 145 255 110 144 254
Sensitivity n/N (%, 95 CI) 105/110 (95.5%, 89.7–98.5) 94/110 (85.5%, 77.5–91.5) 79/110 (71.8%, 62.4–80.0)
Specificity n/N (%, 95 CI) 144/145 (99.3%, 96.2–99.9) 136/145 (93.7%, 88.5–97.1) 144/144 (100.0%, 97.5–100.0)
PPV n/N (%, 95 CI) 105/106 (99.1%, 94.9–99.9) 94/103 (91.3%, 84.1–95.9) 79/79 (100.0%, 95.4–100.0)
NPV n/N (%, 95 CI) 144/149 (96.6%, 92.3–98.9) 136/152 (89.5%, 83.5–93.9) 144/175 (82.3%, 75.8–87.6)
OPA n/N (%, 95 CI) 249/255 (97.6%, 94.9–99.1) 230/255 (90.2%, 85.9–93.6) 223/254 (87.8%, 83.1–91.6)
  1. NPV negative predictive value, OPA overall percentage agreement, PPV positive predictive value
  2. acobas Liat Strep A (POC) and Solana GAS NAAT (laboratory based). PCR via Clopper–Pearson (exact)
  3. bResults based on concordant test results or bidirectional DNA sequencing when results were discordant