[Retracted] Diagnosis and Etiological Analysis of Gastroesophageal Reflux Disease by Gastric Filling Ultrasound and GerdQ Scale

Table 2

The positive and negative predictive values of the two methods were compared.

Golden standard	Ultrasound		GerdQ		Sum
	Positive	Negative	Positive	Negative
GERD	55	7	45	17	62
Non-GERD	7	31	18	20	38
Sum	62	38	63	37	100

Note. The gold standard is endoscopic examination; the GERD group was positive and the non-GERD group was negative.