In Reply Our recent article1 found that higher adenoma detection rates were associated with lower risk of postcolonoscopy colorectal cancer, supporting use of adenoma detection rate as a quality metric. Regarding Dr Colloff鈥檚 inquiry, adenoma detection rates varied across sites and over time. Data included adenoma detection rates from as early as 2011, prior to systematic efforts at improving adenoma detection rates. Adenoma detection rate monitoring and training programs were started first at Kaiser Permanente Northern California, which may account for the higher adenoma detection rates at that site. Comparable associations between adenoma detection rate and postcolonoscopy colorectal cancer were found across all sites (Kaiser Permanente Northern California hazard ratio per 1% absolute adenoma detection rate increase, 0.97 [95% CI, 0.96-0.98]; Kaiser Permanente Southern California hazard ratio per 1% absolute adenoma detection rate increase, 0.97 [95% CI, 0.96-0.99]; and Kaiser Permanente Washington hazard ratio per 1% absolute adenoma detection rate increase, 0.96 [95% CI, 0.93-0.99]).