Robert Leopold Spitzer (May 22, 1932 – December 25, 2015) was a psychiatrist and professor of psychiatry at Columbia University in New York City. He was a major force in the development of the Diagnostic and Statistical Manual of Mental Disorders (DSM). Education and early years Spitzer was born in White Plains, New York, in 1932. He received his bachelor's degree in psychology from Cornell University in 1953 and his M.D. from New York University School of Medicine in 1957. He completed his psychiatric residency at New York State Psychiatric Institute in 1961 and graduated from Columbia University Center for Psychoanalytic Training and Research in 1966. Spitzer wrote an article on Wilhelm Reich's theories in 1953 which the American Journal of Psychiatry declined to publish. Career Spitzer spent most of his career at Columbia University in New York City as a Professor of Psychiatry until he retired in 2003. He was on the research faculty of the Columbia University Center for Psychoanalytic Training and Research where he retired after 49 years in December 2010. He has been called one of the most influential psychiatrists of the 20th century. The Lancet's obituary described him as "Stubborn, sometimes abrasive, and always eager, Spitzer's work was guided by a strong sense of ethical fairness". A colleague at Columbia has described him as an "iconoclast" who "looked for injustice". Screening and Diagnostic Tools Spitzer was a major architect of the modern classification of mental disorders. In 1968, he co-developed a computer program, Diagno I, based on a logical decision tree, that could derive a diagnosis from the scores on a Psychiatric Status Schedule which he co-published in 1970 and that the United States Steering Committee for the United States–United Kingdom Diagnostic Project used to check the consistency of its results. Spitzer was a member on the four-person United States Steering Committee for the United States–United Kingdom Diagnostic Project, which published their results in 1972. They found the most important difference between countries was that the concept of schizophrenia used in New York was much broader than the one used in London, and included patients who would have been termed manic-depressive or bipolar. He developed psychiatric methods that focused on asking specific interview questions to get at a diagnosis as opposed to the open-ended questioning of psychoanalysis, which was the predominant technique of mental health. He codeveloped the Mood Disorder Questionnaire (MDQ), a screening technique