Benedikt R A, Kolb L C
Am J Psychiatry. 1986 Jul;143(7):908-10. doi: 10.1176/ajp.143.7.908.
Of 225 patients referred to a Veterans Administration pain clinic for treatment of chronic pain, 22 (10%) were later diagnosed as having posttraumatic stress disorder. Many of the 22 also had current or past histories of depression, anxiety, or substance abuse.