The Journal of Managed Care Pharmacy published a study examining programs to promote cost-effective use of medication, especially for mental illnesses.  The authors found that the program did not increase costs dramatically and was successful in keeping patients from being hospitalized for mental health treatment.

Simeone, J.C., Marcoux, R.M. and Quilliam, B.J.  (2010).  Cost and utilization of behavioral health medications associated with rescission of an exemption for prior authorization for severe and persistent mental illness in the vermont medicaid program.  Journal of Managed Care Pharmacy, 16(5): 317-328.  http://www.unboundmedicine.com/medline/ebm/record/20518584/abstract/Cost_and_utilization_of_behavioral_health_medications_associated_with_rescission_of_an_exemption_for_prior_authorization_for_severe_and_persistent_mental_illness_in_the_vermont_medicaid_program_  

Authors: J.C. Simeone, R.M. Marcoux and B.J. Quilliam