A new Northwestern Medicine study suggests that a structured simulation‑based training program can significantly improve how gastroenterologists remove precancerous colon polyps, according to findings published in Gastroenterology. 

Investigators found that after completing a simulation‑based mastery learning curriculum, gastroenterologists nearly doubled their rate of performing polypectomies — a core procedure for colorectal cancer prevention — at or above the minimum passing standard, rising from 37 percent before training to 74 percent afterward. The minimum passing standard was set at a very high level of skill. 

The findings represent the first evidence that simulation‑based polypectomy training can translate into improved performance during real-patient procedures, said Srinadh Komanduri, MD, professor of Medicine in the Division of Gastroenterology and Hepatology, who was first author of the study. 

“In the U.S., when you finish training, your competency is assessed only by a written test not procedurally. In addition, there are limited training opportunities for practicing gastroenterologists after fellowship, although they are performing very routine procedures like taking out larger polyps in increasing numbers,” Komanduri said.

Although colonoscopy with polypectomy is one of the most frequently performed procedures in gastroenterology, existing research shows wide variation in how clinicians execute key steps of the technique. There is no universal method for removing polyps, and most practicing gastroenterologists rely on skills learned during fellowship — sometimes decades earlier — with little required ongoing assessment, Komanduri said. 

This variability has real consequences, Komanduri said. Studies have shown that colorectal cancers diagnosed within five years of a negative colonoscopy are often linked to residual adenomatous tissue left behind after an incomplete polypectomy. 

Study investigators found similar concerns: before simulation training, only 49 percent of recorded polypectomies included correct identification and treatment of residual polyp tissue. 

“We wanted to utilize the highest degree of assessment in education now, which is mastery learning, and couple it with a very basic skillset that everyone needs — removing polyps during colonoscopy — and see if this type of education could help practicing gastroenterologists improve skillsets.” Komanduri said. 

The simulation curriculum used in the study was multifaceted and included: 

• A simulated skills pretest, 

• Instructional videos and lecture content, 

• Expert‑guided deliberate practice on an ex vivo bovine colon model containing both sessile and stalked polyps, 

• And a skills post-test in which participants had to meet or exceed a predetermined minimum passing standard. 

Investigators then compared gastroenterologists’ performance using nearly 350 de‑identified patient polypectomy videos from before and after the training.  

After undergoing simulation training, gastroenterologists showed significant improvement across multiple areas. The median pass rate jumped from 33 percent to 80 percent, and performance improved in almost every specific technique category, including polyp positioning, lesion evaluation, snare selection and post-polypectomy inspection.  

The improvements occurred regardless of the physician’s years in practice, suggesting that even seasoned clinicians benefit meaningfully from targeted technique retraining. 

“The participants are excellent gastroenterologists, but they all had areas where they could make subtle improvements,” Komanduri said. “The implementation of this training got almost all of them to the highest level for mastery, and it was durable for up to a year.” 

Incomplete polypectomy is considered a major driver of post‑colonoscopy (interval) colorectal cancers. By elevating technical performance in real-world procedures, simulation-based training could play a critical role in reducing these preventable cancers, study authors said. 

“This is yet another example of how Northwestern Simulation has expanded simulation-based mastery learning to another critical clinical skill. Our research has demonstrated again and again that a curriculum founded in simulation with deliberate practice and mastery learning standards improves patient care and outcomes. The simulation-based mastery learning model has been used successfully to train clinicians in procedural skills, team training and communication,” said the study’s senior author Jeffrey Barsuk, ’99 MD, ’02 GME, ’10 MS, the Robert Hirschtick Professor of Medicine in the Division of Hospital Medicine, who also serves as the executive medical director of Northwestern Simulation. “Simulation-based mastery learning was invented by Northwestern faculty and is now being used all over the world to improve patient care.” 

The authors said the work provides strong justification for expanding simulation-based mastery training into wider continuing education programs for core endoscopic skills. 

“This study shows the feasibility of training and improving skillsets using mastery learning in practicing GIs — I think that’s huge,” Komanduri said. “This is simulation‑based training done on an ex vivo model, and really there are no other opportunities like that available to them.” 

Moving forward, Komanduri, Barsuk and their collaborators hope to expand the training to the Northwestern Health Care Network along with other endoscopic skills in gastroenterology, they said. 

The study was supported by grant R21 DK124816-01 from the National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases.