Working with your example: If we assume the government health service is behaving in its own self interest, why would it spend money on test that it knew not to be cost effective? Whereas if the incentives are split between a Dr ordering a test and an insurance company paying for one wouldn't they disproportionately order tests?
More generally, even if its true for particular testing procedures theres lots of low hanging fruit for intervention before things get severe. The most obvious examples would be schemes to get people to stop smoking or lose weight, that the government provides freely because they are less expensive than the projected cost of the illnesses that would arise without such intervention. Also the ability to see a general practitioner more regularly than if you paid per visit means symptoms can be picked up earlier (e.g. if someone has a mild symptom but has to pay to get it checked they are disincentivised to get it checked until it becomes severe.)
Again, AFAIK smokers and the obese are cheaper in the long run because they die faster.
In line with the results of the poll here, a thread for discussing politics. Incidentally, folks, I think downvoting the option you disagree with in a poll is generally considered poor form.
1.) Top-level comments should introduce arguments; responses should be responses to those arguments.
2.) Upvote and downvote based on whether or not you find an argument convincing in the context in which it was raised. This means if it's a good argument against the argument it is responding to, not whether or not there's a good/obvious counterargument to it; if you have a good counterargument, raise it. If it's a convincing argument, and the counterargument is also convincing, upvote both. If both arguments are unconvincing, downvote both.
3.) A single argument per comment would be ideal; as MixedNuts points out here, it's otherwise hard to distinguish between one good and one bad argument, which makes the upvoting/downvoting difficult to evaluate.
4.) In general try to avoid color politics; try to discuss political issues, rather than political parties, wherever possible.
If anybody thinks the rules should be dropped here, now that we're no longer conducting a test - I already dropped the upvoting/downvoting limits I tried, unsuccessfully, to put in - let me know. The first rule is the only one I think is strictly necessary.
Debiasing attempt: If you haven't yet read Politics is the Mindkiller, you should.