Answer: The APC are the ones who make the recommendations and analyzes the policy changes for CMS. It is MedPac that provides the assessments annually of all the Medicare prospective payment systems. They submit their findings and recommendations to Congress.
It is then up to CMS to consider the recommendations and respond to the MedPac and the APC panel. They do not have to accept them if they don't want too.
People with type 1 diabetes don't produce insulin. You can think of it as not having a key. People with type 2 diabetes don't respond to insulin as well as they should and later in the disease often don't make enough insulin
