RT Journal A1 Overall JE, Hollister LE, Kimbell I, Jr., Shelton J T1 EXtrinsic factors influencing responses to psychotherapeutic drugs JF Archives of General Psychiatry JO Archives of General Psychiatry YR 1969 FD July 1 VO 21 IS 1 SP 89 OP 94 DO 10.1001/archpsyc.1969.01740190091013 UL http://dx.doi.org/10.1001/archpsyc.1969.01740190091013 AB VARIABILITY in responses to drug treatments plagues the researcher concerned with evaluating therapeutic efficacy of psychotropic drugs as well as the clinician who uses them in practice. Some of this variability is associated with patient characteristics that can be identified empirically. The purpose of this investigation was to define some of the more important extrinsic (nondrug) factors that influence short-term symptom reduction under a variety of different drug treatments.Numerous studies have shown that the nature of presenting psychopathology is related to a variety of historical, social, and cultural factors.1-4 Several studies have been concerned with the prediction of treatment outcome and subsequent course of illness.5-7 Most of the latter have considered prognosis in a broader sense than considered here, such as the number of days back in the community during an extended period.8 Previous research has suggested that the relevance of