In recent years, psychotherapy has gained widespread acceptance as an effective method of treatment for patients suffering from mental illness. At the turn of the century there were a handful of psychotherapists in this country. Today they number many thousand. Lay acceptance of this form of treatment has been so widespread that the number of patients seeking psychiatric aid has outstripped the available number of psychotherapists.12 Our knowledge of what elements in psychotherapy make it an effective tool in the treatment of psychological disorders, however, has not increased significantly. No research has, of yet, proved that psychotherapy is more effective than any other kind of help-giving.9,10 It is apparent that there is great need to subject the psychotherapeutic situation to investigation, in order to increase our understanding of how psychotherapy works.
Two experimental approaches have been most commonly pursued in the investigation
FRIEDMAN HJ. Patient-Expectancy and Symptom Reduction. Arch Gen Psychiatry. 1963;8(1):61-67. doi:10.1001/archpsyc.1963.01720070063007