Comparison of left versus right lateral starting position on colonoscopy: a systematic review and meta-analysis of randomized controlled trials

Jun Watanabeia,b

Jichi Medical University, Shimotsuke-City, Tochigi, Japan

aDepartment of Surgery, Division of Gastroenterological, General and Transplant Surgery; bDivision of Community and Family Medicine, Jichi Medical University, Shimotsuke-City, Tochigi, Japan

Correspondence to: Jun Watanabe, MD, PhD, Division of Community and Family Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke City, Tochigi, 329-0498, Japan, e-mail: m06105jw@jichi.ac.jp
Received 12 June 2021; accepted 13 July 2021; published online 14 September 2021
DOI: https://doi.org/10.20524/aog.2021.0658
© 2021 Hellenic Society of Gastroenterology

Ann Gastroenterol 2021; 34 (6): 893-893


We read the article by Ramai et al [1] with great interest, and we appreciate the authors’ efforts to assess the efficacy of a right lateral starting position on colonoscopy compared to a left lateral starting position. However, we would like to point out 2 concerns.

First, the authors should follow the Preferred Reporting items for Systematic Review and Meta-Analyses (PRISMA) guidelines [2]. The author should provide details of the predefined protocol and summarize the strength of the evidence for each major result using the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) approach [3]. We evaluated that the certainty of the evidence regarding the rate of cecal intubation and cecal intubation time was moderate, because of imprecision due to the small sample size for the rate of cecal intubation, and low, because of imprecision and risk of bias due to skewed distribution, respectively. The author should state their conclusions, including the strength of evidence.

Second, this was not a first systematic review but an updated review. The previous systematic reviews showed that, similar to the results of their study, right lateral position did not reduce cecal insertion time as in this study, but the supine (mean difference [MD] -41.0 sec, 95% confidence interval [95%CI] -57.3 to -24.7) and tilt-down position (MD -37.3 sec, 95%CI -72.1 to -2.4) reduced mean cecal insertion time for colonoscopy compared with the left lateral position [4,5].

References

1. Ramai D, Singh J, Brooks OW, et al. Comparison of left versus right lateral starting position on colonoscopy:a systematic review and meta-analysis of randomized controlled trials. Ann Gastroenterol 2021;34:699-704.

2. Moher D, Shamseer L, Clarke M, et al;PRISMA-P Group. Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Syst Rev 2015;4:1.

3. Guyatt G, Oxman AD, Akl EA, et al. GRADE guidelines:1. Introduction-GRADE evidence profiles and summary of findings tables. J Clin Epidemiol 2011;64:383-394.

4. Watanabe J, Park D, Kakehi E, Inoue K, Ishikawa S, Kataoka Y. Efficacy and safety of the starting position during colonoscopy:a systematic review and meta-analysis. Endosc Int Open 2020;8:E848-E860.

5. Lin SY, Yaow CYL, Ng CH, Wong NW, Tham HY, Chong CS. Different position from traditional left lateral for colonoscopy?A meta-analysis and systematic review of randomized control trials. Chronic Dis Transl Med 2021;7:27-34.

Notes

Conflict of Interest: None