For the entire sample, the mean perforation length was (0.711 mm, SD = 1.4) and the mean time required to perform the procedure was (5.65 min, SD = 2.26), and out of the entire sample (N = 36), perforations happened in nine cases for a percentage of 25%.

Chi-square test showed a significant association between method used and the occurrence of perforation (chi-square statistic = 8.585, df = 2, p value = 0.014), as shown in Table 1. Also, ANOVA test showed a significant association between method used and the length of perforation (F = 11.031, df = 2, 33, p value < 0.001) where the BAOSFE caused the largest mean length of perforations (3.42 mm) followed by the CAS kit and the balloon (0.5, 0.5 mm). As for the time required to perform the procedures ANOVA test showed a significant association between method used and the time required to perform it (F = 1221.2, df = 2,33, p value < 0.001); CAS kit required the longest time (8.486 min) followed by the balloon then BAOSFE (5.393, 3.073 min) (Table 1).

Table 2 shows the results of logistic regression of method used on the occurrence of perforation, the odds ratio showed significant differences between the balloon technique and the BAOSFE (OR = 0.091, p value = 0.022), and between the CAS kit and the BAOSFE (OR = 0.091, p value = 0.022); however, no significant differences were found between the balloon and the CAS kit (OR = 1,0, p value = 1). It should be noted that the CAS kit was only able to lift the membrane for a maximum of 5 mm.