Prospective, randomized, and active controlled study of the efficacy of alginic acid and antacid in the treatment of patients with endoscopy-negative reflux disease

Table 2 The change in the VAS of heartburn (ITT population)

Unit: cm	Topaal Mean (SE)	Nacid Mean (SE)	Difference	P
Visit 1/baseline Observed data	7.52 (0.42)	7.43 (0.45)	0.09	0.8774
Visit 3/week 7Observed data	1.15 (0.30)	3.06 (0.34)	–1.91	< 0.0001
Change from baseline	–6.39 (0.28)	–4.44 (0.31)	–1.95	< 0.0001

ANCOVA model: Dependent variable = (baseline value) + treatment.