BACKGROUND Colonoscopies are considered to be the primary screening test and gold standard test for colorectal cancer. Position changes during colonoscope withdrawal are believed to be associated with an increased adenoma detection rate (ADR) and polyp detection rate (PDR). However, previous results conflicted, and this study aimed to elucidate the effectiveness of dynamic position changes during colonoscope withdrawal. METHODS The relevant publications were identified by searching the medical databases. The primary outcomes were the ADR and PDR, which were pooled and analyzed. The secondary outcome was the withdrawal time. The studies that supplied the ADR and PDR for different segments of the colon were separated into subgroup analyses. RESULTS Five randomized controlled trials were eligible for analysis. The total ADR was higher with dynamic position changes than with a static position (odds ratio, [OR] 1.34; 95% confidence interval [CI] 1.13-1.59; p < 0.001), with low evidence of between-study heterogeneity (I2 = 0%). Although the total PDR was slightly higher with dynamic position changes than with a static position (OR 1.23; 95% CI 0.88-1.73), there difference was not statistically significant (p = 0.22). The withdrawal time was only increased by 0.47 min (95% CI - 0.11 to 1.06) with dynamic position changes, without statistical significance (p = 0.11). The subgroup analysis showed that the ADR and PDR for the transverse colon were higher with dynamic position changes, with pooled estimates of ADR (OR 1.72; 95% CI 1.02-2.88; p = 0.04) and PDR (OR 1.79; 95% CI 1.08-2.96; p = 0.02). CONCLUSION Dynamic position changes during colonoscope withdrawal increased the total ADR; however, no obvious increase was found in the total PDR. The withdrawal time was not significantly prolonged with dynamic position changes. Subgroup analysis showed that the ADR and PDR in the transverse colon were obviously improved with dynamic position changes.

中文翻译：

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结肠镜撤回过程中动态位置变化的影响：一项随机对照试验的荟萃分析。

背景技术结肠镜检查被认为是结肠直肠癌的主要筛选测试和金标准测试。结肠镜检查停药期间的位置变化被认为与腺瘤检出率（ADR）和息肉检出率（PDR）升高有关。但是，先前的结果相互矛盾，并且本研究旨在阐明结肠镜撤回过程中动态位置变化的有效性。方法通过检索医学数据库来鉴定相关出版物。主要结果是汇总和分析了ADR和PDR。次要结果是退出时间。为结肠的不同部分提供ADR和PDR的研究分为亚组分析。结果五个随机对照试验符合分析条件。动态位置变更的总ADR高于静态位置（赔率，[OR] 1.34； 95％置信区间[CI] 1.13-1.59； p <0.001），并且研究间异质性的证据很少（I2 = 0％）。尽管动态位置变化的总PDR略高于静态位置的总PDR（OR 1.23； 95％CI 0.88-1.73），但差异无统计学意义（p = 0.22）。随着动态位置变化，撤药时间仅增加了0.47分钟（95％CI-0.11至1.06），无统计学意义（p = 0.11）。亚组分析显示，随着动态位置的变化，横结肠的ADR和PDR较高，对ADR（OR 1.72; 95％CI 1.02-2.88; p = 0.04）和PDR（OR 1.79; 95％CI 1.08）进行汇总估计-2.96； p = 0.02）。结论撤回结肠镜时动态位置改变增加了总ADR。但是，总PDR没有明显增加。撤离时间没有随着动态位置变化而明显延长。亚组分析显示，随着动态位置的改变，横结肠中的ADR和PDR明显改善。