Clinical neuropsychology focuses on the brain and goes back to the beginning of the 20th century. As a clinician a clinical neuropsychologist offers their services by addressing three steps; assessment, diagnosis, and treatment. The term clinical neuropsychologist was first made by Sir William Osler on April 16, 1913. While clinical neuropsychology was not a focus until the 20th century evidence of brain and behavior treatment and studies are seen as far back as the neolithic area when trephination, a crude surgery in which a piece of the skull is removed, has been observed in skulls. As a profession, clinical neuropsychology is a subspecialty beneath clinical psychology. During World War I (1914–1918) the early term shell shock was first observed in soldiers who survived the war. This was the beginning of efforts to understand traumatic events and how they affected people. During the Great Depression (1929–1941) further stressors caused shell shock like symptoms to emerge. In World War II (1939–1945) the term shell shock was changed to battle fatigue and clinical neuropsychology became even more involved with attempting to solve the puzzle of peoples' continued signs of trauma and distress. The Veterans Administration or VA was created in 1930 which increased the call for clinical neuropsychologists and by extension the need for training. The Korean (1950–1953) and Vietnam Wars (1960–1973) further solidified the need for treatment by trained clinical neuropsychologists. In 1985 the term post-traumatic stress disorder or PTSD was coined and the understanding that traumatic events of all kinds could cause PTSD started to evolve.