[londons_explore]

> insurers probably have better actuarial data

Imagine you are an insurer and advise free annual checkups. Some of your patients don't bother. Those patients have a higher mortality. You conclude the annual checkup is good.

But you might be deceiving yourself - the kind of people to ignore health advice about getting an annual checkup might also be the kind of people to ignore the health advice on the back of a cigarette packet...

[nradov]

Major medical insurers are not naive about this stuff. They employ expert actuaries and data scientists who understand statistics and causality.

[londons_explore]

Sure, they understand the problem... But is there anything they can do about it?

I'm not aware of insurance companies being too keen on getting into medical experiments like 'people with a birthday on a Thursday don't get the free annual checkup'.