1940

Some 70% of physicians in U.S. still in general practice (Rothman, 114). Three of every four physicians thought of themselves as generalists; by 1966, the proportion was less than one of three (Stevens, 312). Publication of 1st edition of the Directory of Medical Specialists by the Advisory Board for Medical Specialties (Stevens, 260, 266). Approx. 1,000 American physicians view themselves as heart specialists, but few had any formal cardiology training; at the time, there were 451 official residency positions in internal medicine but only four in cardiology (Fye 2, 86). ABIM establishes subspecialties of cardiology, allergy, gastroenterology, and pulmonary disease (Howell II, 772-73).