Background: There has been little reported experience in the Latin American hospital setting in relation to the impact of the endoscopic training process on colonoscopy quality. Aims: To determine the effect that training in the technique of colonoscopy has on adenoma detection in an Argentinian teaching hospital. Material and method: Within the time frame of July 2012 and July 2013, 3 physicians received training in colonoscopy from 4 experienced endoscopists. The colonoscopies performed by the supervised trainees were compared with those carried out by the experienced endoscopists. Results: A total of 318 colonoscopies performed by any one of the 3 supervised trainees and 367 carried out by any one of the experienced endoscopists were included. The univariate analysis showed a non-significant difference in the detection rate of adenomas (30.4 vs 24.7%, P = .09). In the multivariate analysis, the detection rate of adenomas was significantly higher in the colonoscopies performed by one of the 3 trainees (odds ratio = 1.72 [1.19-2.48]). Conclusions: The supervised involvement of endoscopic trainees has a positive effect on adenoma detection.