Table 5.

Diagnostic Accuracy of Gastroesophageal Reflux Disease Questionnaire Compared to Other Diagnostic Tools

	Prevalence	Sensitivity	Specificity	PPV	NPV	Accuracy
GerdQ vs. Endoscopy	43.65	74.55	73.24	68.33	78.79	73.81
GerdQ vs. pH-metry	49.30	67.14	72.22	70.15	69.33	69.72
GerdQ vs. Endoscopy + pH-metry	71.43	71.67	72.22	86.58	50.49	71.83
Prior diagnosis vs. Endoscopy	43.65	53.64	71.83	59.60	66.67	63.89

PPV, positive predictive value; NPV, negative predictive value; GerdQ, gastroesophageal reflux disease questionnaire. Data are presented as %.