In the UK there is a department called NICE which uses health economics to understand how to best utilize the funding for the national health service to best improve health outcomes (generally measured by increasing QALY or Quality-Adjusted Life Years, but there are multiple measures in reality). This means that if there is a £500k treatment that could save the lives of a 70 year old, but there is a £1m treatment that could save the life of a 20 year old, and there is only budget for one, it would go to the £1m treatment because it has the biggest impact on QALY.
So the treatments that don't get approval are usually those that have a poor return. Note that it's usually the whole treatment that gets approved / denied rather than particular patient (or it is approved for a particular subset of people).
The other issue is capacity - so for instance, if there is only a limited capacity to perform MRI scans, then triage is required.
It's worth mentioning that in the UK you can still pay for private treatment, and thus avoid any queues. You can also buy insurance to pay for private treatment.
I know this is tongue in cheek, but all these countries also have private health options, so it’s not really a genuine argument against it anyways. If you were too poor to afford good coverage in the US, you wouldn’t be able to afford the private coverage in other countries either, but for rich people, private insurance is easily obtainable, for relatively cheap too, since they compete with “free”.
In the UK there is a department called NICE which uses health economics to understand how to best utilize the funding for the national health service to best improve health outcomes (generally measured by increasing QALY or Quality-Adjusted Life Years, but there are multiple measures in reality). This means that if there is a £500k treatment that could save the lives of a 70 year old, but there is a £1m treatment that could save the life of a 20 year old, and there is only budget for one, it would go to the £1m treatment because it has the biggest impact on QALY.
So the treatments that don't get approval are usually those that have a poor return. Note that it's usually the whole treatment that gets approved / denied rather than particular patient (or it is approved for a particular subset of people).
The other issue is capacity - so for instance, if there is only a limited capacity to perform MRI scans, then triage is required.