They made a guesstimate, an arbitrary demarcation to say how many would be missed if those patients had just a sigmoidoscopy. They found about 1-2% of people with advanced proximal neoplasia would be missed if they came to screening and had a flexible sigmoidoscopy. That’s what drives the notion that everybody should have a colonoscopy and not a sigmoidoscopy. Older age is at risk probably because as we age there is a greater likelihood for the proximal colon to develop problems, and men seem to be at higher risk in these studies. I’ve played with their definition of advanced, and if I only look at high grade dysplasia and cancer, in fact only 15% of the advanced adenomas would be missed or only 0.4% overall in the population. It starts to become a much smaller number. Then you have to be concerned about the risks of the colonoscopy, which is .32% with major morbidity at 30 days. It’s not absolute here that everybody should have a colonoscopy, or at least, one has to be cognizant of some of the limitations.