Low-dose amitriptyline combined with proton pump inhibitor for functional chest pain

Figure 2 Efficacy of both treatment groups on the global symptom score. The global symptom scores over time was associated with each treatment. The overall mean difference between the two groups was not significantly different (P = 0.172). However, we found that the time effect and time × group interaction effect were significant (P < 0.001 and P = 0.006, respectively). Consequently, the between-group difference in global symptom scores was statistically significant at the last week (P < 0.001).