Medical Clearance

Today is the day President Donald Trump will be experiencing his first medical evaluation in the White House. ACSH's Dr. Jamie Wells discussed with BBC TV's anchor Matthew Amroliwala the many misperceptions and falsehoods that have abounded in the media surrounding such an event. 
With President Trump's annual physical looming, what matters most? And specifically, what would it take to make a president unfit to serve? 
With medical fitness to serve being a recurring theme in 2016, Santa Claus requested his doctor release his latest health report. Will he be cleared by Christmas?
With medical letters and the general health of the presidential candidates recently being the big topic of discussion, who's medically fit or unfit in 2016?  What condition would cause you, or a major party, to disqualify someone running for President of the United States? (The answer is different for a physician.)