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I would like to thank Dr Paspatis for the very thoughtful comments on our article regarding the use of high-definition colonoscopy. Indeed, the comments by Dr Paspatis support the conclusion that high-definition colonoscopy is associated with higher detection rates of overall polyps and, to a lesser extent, adenomatous polyps.Of the 5 studies reviewed in Table 1, 4 showed numerically higher rates of detection for polyps and adenomas, and 1 study showed essentially identical rates for standard versus high-definition colonoscopy. Although the design and power of each of these studies vary, in aggregate, they provide strong evidence that these advances yield to greater detection of polyps in patients undergoing screening and surveillance colonoscopy. The differences in the studies cannot be entirely explained by their design.Most of the differences, however, are related to the sample size and the relative power to assess small differences. Our study, being the largest of the studies by almost 3-fold, suggests that the statistical significance seen in detection of both adenomas and overall polyps may be owing to the greater sample size. In all studies, the differences between the standard definition and high-definition colonoscopies were relatively small and largely restricted to small polyps.Other key differences in the studies were whether it was a prospective randomized trial versus an observational study. Both designs have merit, with prospective randomized trials providing the most precise estimate of differences between the 2 arms; however, the observational design used in our study may provide a more accurate estimate of the true rates in clinical practice.A common negative finding of all these studies was the absence of significant differences in detection of advanced and flat adenomas. Again, this may be owing to the rarity of these lesions and the lack of statistical power to assess for small differences. It is important to note that differences in technique such as careful attention to looking behind colonic folds, washing mucus from the surface, and spending sufficient inspection time are likely of much greater importance for improving the overall quality of colonoscopy. I would like to thank Dr Paspatis for the very thoughtful comments on our article regarding the use of high-definition colonoscopy. Indeed, the comments by Dr Paspatis support the conclusion that high-definition colonoscopy is associated with higher detection rates of overall polyps and, to a lesser extent, adenomatous polyps. Of the 5 studies reviewed in Table 1, 4 showed numerically higher rates of detection for polyps and adenomas, and 1 study showed essentially identical rates for standard versus high-definition colonoscopy. Although the design and power of each of these studies vary, in aggregate, they provide strong evidence that these advances yield to greater detection of polyps in patients undergoing screening and surveillance colonoscopy. The differences in the studies cannot be entirely explained by their design. Most of the differences, however, are related to the sample size and the relative power to assess small differences. Our study, being the largest of the studies by almost 3-fold, suggests that the statistical significance seen in detection of both adenomas and overall polyps may be owing to the greater sample size. In all studies, the differences between the standard definition and high-definition colonoscopies were relatively small and largely restricted to small polyps. Other key differences in the studies were whether it was a prospective randomized trial versus an observational study. Both designs have merit, with prospective randomized trials providing the most precise estimate of differences between the 2 arms; however, the observational design used in our study may provide a more accurate estimate of the true rates in clinical practice. A common negative finding of all these studies was the absence of significant differences in detection of advanced and flat adenomas. Again, this may be owing to the rarity of these lesions and the lack of statistical power to assess for small differences. It is important to note that differences in technique such as careful attention to looking behind colonic folds, washing mucus from the surface, and spending sufficient inspection time are likely of much greater importance for improving the overall quality of colonoscopy. How Strong Is the Evidence That High-Definition Colonoscopy Improves Polyp Detection Rate Compared With Standard White-Light Colonoscopy?Clinical Gastroenterology and HepatologyVol. 8Issue 10PreviewWe read with interest the article by Buchner et al1 on the higher rate of colorectal polyp detection with high-definition (HD) colonoscopy against standard (SD) white-light colonoscopy. A limited number of studies have compared the efficacy of HD versus SD colonoscopy for polyp detection. Not all studies corroborated the superiority of high-definition imaging with conflict of results. Comparisons of adenoma and polyp detection rate according to HD and SD colonoscopy for the existing studies are summarized in Table 1. Full-Text PDF