Cf o contexto abaixo (fonte: site oficial do Medicare).

APPEAL
An appeal is a special kind of complaint you make if you disagree with a decision to deny a request for health care services or payment for services you already received. You may also make a complaint if you disagree with a decision to stop services that you are receiving. For example, you may ask for an appeal if Medicare doesn't pay for an item or service you think you should be able to get. There is a specific process that your Medicare Advantage Plan or the Original Medicare Plan must use when you ask for an appeal.
Babylon Medicare Glossary

Your Medicare Appeal Rights:
You have the right to appeal any decision about your Medicare services. This is true whether you are in Original Medicare, a Medicare managed care plan, or a Medicare prescription drug plan. If Medicare does not pay for an item or service you have been given, or if you are not given an item or service you think you should get, you can appeal.
http://www.medicare.gov/basics/appeals.asp