Posted on May 19, 2022

In Case You Missed It: Seminal RCTs Changing Clinical Practice Guidelines 

Philip Schoenfeld, MD, MSEd, MSc (Epi)

Chief (Emeritus)-Gastroenterology Section, John D. Dingell VA Medical Center, Detroit, MI

Welcome to a new series, In Case You Missed It, which will summarize landmark randomized controlled trials (RCTs) from the past 3-5 years that impact clinical practice guidelines. Consistent with our mission at Evidence-Based GI, summaries will focus on RCTs published in non-GI journals (e.g., New England Journal of Medicine, JAMA, Annals of Internal Medicine, etc.) and provide structured abstracts about study design and results. 

 As I noted in my introductory editorial from October 2021, Evidence-Based GI is a work in progress where the content may change over time. This new series arose because our Associate Editors wanted to highlight seminal RCTs that changed recent clinical practice guidelines, regardless of whether or not they were published in the past 12 months. Emphasizing this research is worthwhile since compliance with clinical practice guidelines is often sub-optimal. For example, Dr. Swati Patel’s summary of the ground-breaking PLCO study reminds us that average-risk individuals with 1-2 non-advanced adenomas have similar risk of colorectal cancer (CRC) as average-risk individuals with no adenomas.1 This study, which was published in JAMA in 2018, was critical to the 2020 US Multi-Society Task Force on CRC recommendation that extended surveillance intervals from 5-10 years to 7-10 years among average-risk individuals with 1-2 non-advanced adenomas.2  Yet, multiple studies show that endoscopists frequently recommend intervals shorter than 5 years for these individuals.3  

 Although strong guideline recommendations should be applied to most patients, we also recognize that mindless application of RCT results to patient care is sub-optimal or even harmful. Thus, appropriate application of evidence-based medicine (EBM) recognizes the importance of the other “EBM”: experience-based medicine. Therefore, these summaries provide standardized commentary, including sections such as “Caution,” which discusses study limitations, as well as “My Practice,” which describes how our Associate Editors combine evidence and experience to the treatment of individual patients.   

 We continue to make adjustments in format and presentation. Over the past 3 months, Joseph Sleiman, MD, our Associate Editor for Social Media, has expanded our outreach with weekly tweetorials. We’re reaching out directly to GI fellows and GI fellowship program directors since Evidence-Based GI is a great resource for their journal clubs. I continue to welcome your comments and feedback and thanks for reading.  


  1. Click B, Pinsky PF, Hickey T, Doroudi M, Schoen RE. Association of Colonoscopy Adenoma Findings with Long-Term Colorectal Cancer Incidence. JAMA 2018; 319: 2022-31.  
  2. Gupta S, Lieberman D, Anderson JC, et al. Recommendations for Follow-Up After Colonoscopy and Polypectomy: A Consensus Update by the US Multi-Society Task Force on Colorectal Cancer. Am J Gastroenterol 2020: 115: 415-34. 
  3. Petros V, Tsambikos E, Madhoun M, Tierney B. Impact of Community Referral on Colonoscopy Quality Metrics in a Veterans Affairs Medical Center. Clin Translational Gastroenterol 2022; 13: 1-9. Schoenfeld May Editorial

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