Supplementary Material for: Efficacy and safety of cold snare polypectomy versus cold endoscopic mucosal resection for resecting 3–10 mm colorectal polyps: Systematic review and meta-analysis of randomized controlled trials

Abstract
Introduction The safety and efficacy of cold snare polypectomy (CSP) compared to those of cold endoscopic mucosal resection (CEMR) have been reported. This meta-analysis compared the efficacy and safety of CEMR and CSP.
Methods PubMed, EMBASE, Web of Science, and Cochrane Library databases were systematically searched to identify randomized controlled trials comparing the efficacy and safety of CEMR and CSP in removing 3–10 mm polyps. The outcomes assessed included complete resection rate, intraoperative bleeding rate, delayed bleeding rate, perforation, and polyp removal time. The results are reported as risk ratios (RR) and 95% confidence intervals (CI) derived from a Mantel–Haenszel random effects model.
Results Seven studies comprising 1,911 polyps were included in the analysis. The complete resection rate of CEMR was comparable to that of CSP (RR: 1.01, 95% CI: 0.99–1.04, P = 0.32). Comparable results were also demonstrated for intraoperative bleeding rate (polyp-based analysis: RR: 1.22, 95% CI: 0.33–4.43, P = 0.77), delayed bleeding rate (polyp-based analysis: RR: 1.34, 95% CI: 0.44–4.15, P = 0.61), and polyp removal time (mean difference: 28.31 s, 95% CI: -21.40~78.02, P=0.26). No studies reported cases of perforation.
Conclusion CEMR has comparable efficacy and safety to CSP in removing 3–10 mm polyps. Further randomized controlled trials with long-term follow-up are warranted to compare and validate efficacy.

摘要
## 引言
已有研究针对冷圈套器息肉切除术（cold snare polypectomy, CSP）与冷内镜黏膜切除术（cold endoscopic mucosal resection, CEMR）的安全性与有效性展开对比报道。本荟萃分析旨在比较CEMR与CSP的临床疗效及安全性。
## 方法
系统检索PubMed、EMBASE、Web of Science及Cochrane Library数据库，筛选对比CEMR与CSP切除3~10 mm息肉的疗效及安全性的随机对照试验。本研究的评估结局指标包括完整切除率、术中出血率、迟发性出血率、穿孔发生率及息肉切除时间。研究结果采用Mantel-Haenszel随机效应模型计算得到的风险比（risk ratios, RR）与95%置信区间（95% confidence intervals, CI）进行报告。
## 结果
本分析共纳入7项研究，涉及1911枚息肉。CEMR的完整切除率与CSP相当（RR=1.01，95%CI：0.99~1.04，P=0.32）。术中出血率（以息肉为单位的分析：RR=1.22，95%CI：0.33~4.43，P=0.77）、迟发性出血率（以息肉为单位的分析：RR=1.34，95%CI：0.44~4.15，P=0.61）及息肉切除时间（均数差=28.31s，95%CI：-21.40~78.02，P=0.26）的对比结果亦无显著差异。所有纳入研究均未报告穿孔病例。
## 结论
在切除3~10 mm息肉时，CEMR与CSP的疗效及安全性相当。未来仍需开展纳入长期随访的随机对照试验，以进一步对比并验证二者的临床疗效。