Diagnostic testGastric pH versus all other samples (95% CI)
Sensitivity %68 (57, 77)71 (55, 84)65 (51, 77)73 (57, 85)
Specificity %79 (74, 84)77 (69, 84)81 (74, 86)79 (70, 85)
PPV %52 (45, 58)52 (42, 61)52 (43, 61)53 (44, 62)
NPV %88 (85, 91)89 (83, 93)88 (84, 91)90 (83, 92)
PLR3.3 (2.5, 4.2)3.1 (2.1, 4.5)3.4 (2.3, 4.9)4.0 (2.4, 5.7)
NLR0.4 (0.3, 0.6)0.4 (0.2, 0.6)0.4 (0.3, 0.6)0.4 (0.3, 0.6)
Overall accuracy† %76 (72, 81)76 (68, 82)77 (68, 82)77 (70, 83)
  • *Confounding included antacid medication, pernicious anaemia or gastric surgery.

  • †Refers to the probability that the aspirate will be correctly identified.

  • NLR, negative likelihood ratio; NPV, negative predictive value; PLR, positive likelihood ratio; PPV, positive predictive value.