Table 3 Characteristics of heartburn and regurgitation.

	Heartburn	Regurgitation	p Value
pH drop	3.5 (1.9–4.4)	2.6 (1.8–4.5)	0.7
Nadir pH	2.2 (1.8–3.3)	2.3 (1.9–3.2)	0.7
Proximal extent (cm)	11 (9–15)	15 (11–18)	0.002
Ascending velocity (cm/s)	5.0 (3.3–9.2)	6.0 (3.2–8.8)	0.9
Volume clearance (s)	13 (8–21)	11 (8–18)	0.4
Acid clearance (s)	57 (30–120)	60 (30–100)	0.9

Values are median (interquartile range).