One Colonoscopy, Thirteen Years, and a Mortality Signal That Didn’t Arrive: What the NordICC Trial Really Breaks (The Clinical Trial Vanguard)

Picture a statistician in Oslo in 2009, working backward from a mortality assumption to calculate the sample size her trial would need. The number she anchored on: a baseline colorectal cancer mortality incidence rate of 0.82% in the no-screening population. That figure was not invented — it reflected the epidemiological reality of the era. It became the load-bearing assumption beneath the entire NordICC trial, and thirteen years later, it collapsed. The observed colorectal cancer mortality in the no-screening group at 13 years came in at 0.47% — nearly half the projected rate. The trial was powered for a world that no longer existed by the time the data matured.