[jahnu]

Aye that’s a great one. Even testing and treating not so rare conditions can lead to statements that seem different when you know the details.

Imagine you test early and often for a condition in country A much more often than country B which waits until some more late stage easier to detect symptoms occur. Now compare survivor rates. Much higher in country A! We should clearly also be testing in country B, right?

Depends. If the condition is something that doesn’t often actually kill and typically remains at a non lethal but detectable state then all you might have done is treat a lot of extra non fatal conditions that usually only is detected in country B once it evolves to a more advanced and dangerous state. You may have put many people in country A through an unnecessary, expensive, and frightening treatment regime.

The point is that these things are complex and need thorough analysis.