A focus of Austrian science has always been medicine and psychology, starting in medieval times with Paracelsus. Eminent physicians like Theodore Billroth, Clemens von Pirquet, and Anton von Eiselsberg have built upon the achievements of the 19th-century Vienna School of Medicine. Austria was home to Sigmund Freud, founder of psychoanalysis, Alfred Adler, founder of Individual psychology, psychologists Paul Watzlawick and Hans Asperger, and psychiatrist Viktor Frankl. Austria was ranked 19th in the Global Innovation Index in 2020, up from 21st in 2019.