Statistical analysis
EVENTS, SEPARATION
The sample size was calculated based on the primary studies. The treatment difference assumption was mainly based on another studyAdverse events were organized by our study group and presented as the number and proportion of patients. For other surgical information, the surgical time was defined as the interval between the start and completion of oesophageal ESD. The cutting time was the interval between the start of the resection and complete separation of the specimen. Moreover, the protective gel injection time and the wound coverage by gel were also calculated among the experimental groups.The results are presented as the mean ± standard deviation or counts (percentages). The t-test was used for data analysis. All 