Let's say you suddenly lose your ability to speak, you think it's a stroke, so you head to the closest clinic. They freak out because you need to go to a stroke center. People (or their family) often ask "What's the best stroke center around here? I want to go there!".
If they had the info available to them, why couldn't they include cost in that equation?
If I assume that the relative differences that Medicare has negotiated are similar to the relative differences my insurance company has negotiated (which I'm guessing is an invalid assumption), and if I accurately know what my policy will cover vs not cover (again, a nearly impossible thing to know given how complicated these things are), then maybe you can make a decision with this data. But the system is so complicated that I don't think that works at all by just using this dataset.
If the population goes to a number of different providers, then the insurance company can play hardball and say "if you don't take this rate, you're out of our network, good luck with that". In those cases, they'll negotiate an MS-DRG + X% rate.
The reason why negotiated rates with private insurers are non-public is because it's a negotiating tool. If hospital A gets paid $5K for a heart attack and finds out hospital B a block away gets paid $7K for the same thing, the next round of negotiations will be very rowdy.
US Patients go to south america and Asia to get treated. I don't think shopping around the country hospitals to figure out a good option is going to be a big problem. This is a good first step.
A hospital with a cost of $20K for a procedure might only get paid $5K, while one with a $10K cost might get paid $8K!
In fact, the same hospital can get paid very differently between different insurance companies.
That is a plausible but false assumption. Different providers negotiate different rates. In many cases, the negotiated rate for a given provider is lower than the "cash rate" that an uninsured person would pay, but in many cases the negotiated rate it is actually much higher(!). Maybe in these cases the insurer gets an end-of-year volume-based discount that the insured (me) never gets to see.
Source: my recent experience shopping for an MRI while on a high-deductible plan.