This article examines the variables associated with reduced medical utilization following mental health treatment.  The outcomes of all of the studies examined ranged from a 72.4% increase to –181.6% (decrease) in use of medical services following psychotherapy. Eighty-five percent of all of these studies reported a decrease in medical utilization following psychotherapy. The authors conclude that there is evidence of a general cost-offset following mental health treatment. 

Mumford, E., Schlesinger, H. J., & Glass, G. V. et al. (1998). A new look at evidence about reduced cost of medical utilization following mental health treatment. Journal of Psychotherapy Practice and Research, 7: 65-86.  http://jppr.psychiatryonline.org/cgi/content/full/7/1/65a 

Authors: Emily Mumford, Herbert J. Schlesinger, Gene V. Glass, Cathleen Patrick, Timothy Cuerdon