Thank you.
The incidence change in Canada was different from the incidence in the United States. That may be one reason.
Dr. Paula Gordon explained the difference in the two types of interval cancers. It's important to understand, exactly as Dr. Gordon said, that this is why screening doesn't help for some interval cancers. The more aggressive ones appear between screens. Although screening does help for some, it doesn't help for all.
Another important thing about interval cancers or detecting cancer early is that we don't necessarily know that screening will change the outcomes. This is something called length-time bias. A more slowly growing cancer will sit and wait and not present as a lump until a screen. A more aggressive cancer will show up in between screens. Obviously, when we look back at retrospective studies, it looks like screening catches all the very slow-growing cancers and it looks like all the fast-growing ones are in people who don't have screening, but that's because they're fast, and they show up as interval cancers. That's called length-time bias. It's a very important bias. We don't dismiss studies because of it, but we always have to think that this bias is there. The task force has to look at all of that data as systematically and as methodically as possible.
Finally, with regard to the U.S., they actually acknowledge in their guidelines that the recommendation doesn't actually improve EDI, or equity and diversity. They actually say in their guidelines that starting everybody at 40 doesn't actually improve the disparities.
We all call for more research in that area.