Cost and cost-effectiveness of three strategies for implementing motivational interviewing for substance misuse on medical inpatient units.

Background: This study conducted cost and cost-effectiveness analyses of three strategies for implementing motivational interviewing for substance misuse on general medical inpatient units: workshop, apprenticeship, and consult.

Methods: The economic analyses were conducted prospectively alongside a type 3 hybrid effectiveness-implementation randomized trial comprising 38 medical providers, 1173 inpatients, and four consultation-liaison motivational interviewing experts. The trial took place in a university affiliated teaching hospital in New Haven, CT, USA. After completing a 1-day workshop on motivational interviewing, providers were randomized to conditions. The primary outcome measure was the number of study-eligible patients who received a motivational interview. The economic analyses included the costs of both start-up and on-going activities in each condition. Incremental cost-effectiveness ratios were used to determine cost effectiveness. Results are presented from the healthcare provider (i.e., hospital) perspective in 2018 US dollars.

Results: The total cost per patient receiving a motivational interview averaged $804.53, $606.52, and $185.65 for workshop, apprenticeship, and consult, respectively. Workshop and apprenticeship were extended dominated by the combination of consult and doing nothing. Doing nothing is cost effective when the willingness-to-pay for an additional patient receiving a motivational interview is less than $185.65, and consult is cost-effective when the willingness-to-pay for an additional patient receiving a motivational interview is greater than $185.65.

Conclusions: Given that typical reimbursements for brief intervention services for substance misuse are $35-$65, none of the three implementation strategies is likely to be economically viable from the healthcare provider perspective.