Clinic variation in the cost-effectiveness of contingency management.

This study determined whether, and by how much, the cost-effectiveness of contingency management (CM) varied across the eight clinics in the National Institute on Drug Abuse Clinical Trials Network MIEDAR trial. Incremental costs, incremental outcomes, and incremental cost-effectiveness ratios (ICERs) of CM compared to usual care were calculated, compared and contrasted for each of the clinics. Results showed that the incremental cost of using CM compared to usual care varied by a factor of 1.9 across the clinics, ranging from an additional $306 to an additional $582 per patient. The effect of CM on the longest duration of continuous stimulant abstinence (LDA) varied by a factor of 8.0 across the clinics, ranging from an additional 0.5 to an additional 4.0 weeks. The ICERs for the LDA varied by a factor of 4.6 across the clinics, ranging from $145 to $666. These results show that the cost-effectiveness of CM varied widely among the clinics in the MIEDAR trial. Future research should focus on identifying the sources of this variation, perhaps by identifying clinic-level best practices and/or identifying those subgroups of patients that respond the most cost-effectively, with the ultimate goal of improving the cost-effectiveness of CM overall.