[lesuorac]

IIUC, the difference (for USG) of Medicare vs Medicare Advantage is that Medicare subsidizes the cost of a procedure done by a provider while Medicare Advantage (MA) pays a fixed rate per treatment to an insurer.

So if the MA rate is less than the provider changes then the insurer is highly incentivized to deny you coverage. While for Medicare you'd have a higher co-pay.

This also leads to scenarios where MA insurers upcode patients so that the treatment is at a higher rate [1]. (ex. Marking patients as recovering drug addicts when prescribing opioids to get both money from both counseling and the opioid treatment).

[1]: https://www.healthcaredive.com/news/unitedhealth-grassley-me...