Table 5.

Test Characteristics of the Response to Proton Pump Inhibitor Treatment in the Diagnosis of Gastroesophageal Reflux Disease

Decrease in GerdQ score	Sensitivity % (95% CI)	Specificity % (95% CI)	PPV % (95% CI)	NPV % (95% CI)
≥ 1	93.0 (88.3–97.7)	48.6 (32.0–65.1)	85.5 (79.3–91.7)	68.0 (49.7–86.3)
≥ 2	78.9 (71.5–86.4)	80.0 (66.7–93.3)	92.8 (87.6–98.0)	53.8 (40.3–67.4)
≥ 3	56.1 (47.0–65.2)	94.3 (86.6–102.0)	97.0 (92.8–101.1)	39.8 (29.2–50.3)

NPV, negative predictive value; PPV, positive predictive value; GerdQ, Gastroesophageal Reflux Disease Questionnaire.