This article concludes that the current information is not sufficient to assess to utility of substance abuse spending levels.  The authors develop and present a framework for assessing the optimal level of substance abuse expenditures focusing on treatment recipients, quality of treatment, and the relationship between treatments and outcomes. 

Meara, E., & Frank. R. G. (2005). Spending on substance abuse treatment: how much is enough? Addiction, 100(9), 1240-48. DOI: 10.1111/j.1360-0443.2006.01390.x.* *Note: A standard hyperlink is not available for this citation; however, this article’s abstract is accessible via the Digital Object Identifier (DOI) provided here. 

Authors: Ellen Meara and Richard G. Frank