The most wealthy physician billionaires on Forbes' real-time billionaire tracker are varying degrees of self-made. Thomas Frist Jr., MD, the richest self-made physician billionaire in the U.S. — worth $21.1 billion — earned a "self-made" score of seven.
Forbes scores each of its listed billionaires with a "self-made" score ranging from one to 10, with one through five indicating someone who inherited some or all of his or her fortune; while six through 10 are for those who built their company or established a fortune on his or her own.
Dr. Frist got a head start from wealthy parents and an affluent background, but is primarily responsible for his own fortune.
A former Air Force flight surgeon, Dr. Frist founded Nashville, Tenn.-based HCA Healthcare with his father in 1968. He owns more than 20 percent of the company. Although he does not hold an executive position at HCA, his sons are board members.
Editor's note: Live net worth data collected Sept. 22.