Validity of studies suggesting preoperative chemotherapy for resectable thoracic esophageal cancer: A critical appraisal of randomized trials

Figure 4 Meta-analysis of six studies after excluding all studies which found a statistically significant survival advantage in the experimental group. HR: hazard ratio; N(T): Number of patients in the experimental group; N(C): Number of patients in the control group; W(fixed): Weight assigned to the study by using a fixed-effect model; W(random): Weight assigned to the study by using a random-effect model.