Nolan D. C. Lewis remarks4 that "the development of thought and research in psychiatry is really the story of the evolution of the scientific method" and that the first step which characterizes the scientific method is that "the observations must be made and recorded in definite terms." Systematic observation of all cases, not just the novel or particularly interesting case, may be said to have begun with Pinel's appointment to the Bicêtre: "Thus it was Pinel who actually introduced the taking of psychiatric case histories and the keeping of case records. At first the majority of these records were Pinel's personal notes made for his own use, but the principle was established and it proved the cornerstone of a psychiatric research which would have been totally impossible without the permanent, systematic case records which are now the measure and identifying sign of a good mental hospital."
ULLMANN LP, GUREL L. Validity of Symptom Rating from Psychiatric Records. Arch Gen Psychiatry. 1962;7(2):130-134. doi:10.1001/archpsyc.1962.01720020054009