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Washington State Institute for Public Policy
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Motivational interviewing to enhance treatment engagement

Substance Use Disorders: Treatment for Adults
Benefit-cost methods last updated December 2023.  Literature review updated December 2014.
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Motivational interviewing is a non-confrontational technique, used early in treatment, to help clients increase their motivation and commitment to change. Most commonly, motivation interviewing involves one or two individual sessions.
For an overview of WSIPP's Benefit-Cost Model, please see this guide. The estimates shown are present value, life cycle benefits and costs. All dollars are expressed in the base year chosen for this analysis (2022). The chance the benefits exceed the costs are derived from a Monte Carlo risk analysis. The details on this, as well as the economic discount rates and other relevant parameters are described in our Technical Documentation.
Benefit-Cost Summary Statistics Per Participant
Benefits to:
Taxpayers $2,019 Benefits minus costs $7,718
Participants $4,108 Benefit to cost ratio $25.61
Others $316 Chance the program will produce
Indirect $1,589 benefits greater than the costs 56%
Total benefits $8,031
Net program cost ($314)
Benefits minus cost $7,718

^WSIPP’s benefit-cost model does not monetize this outcome.

Meta-analysis is a statistical method to combine the results from separate studies on a program, policy, or topic in order to estimate its effect on an outcome. WSIPP systematically evaluates all credible evaluations we can locate on each topic. The outcomes measured are the types of program impacts that were measured in the research literature (for example, crime or educational attainment). Treatment N represents the total number of individuals or units in the treatment group across the included studies.

An effect size (ES) is a standard metric that summarizes the degree to which a program or policy affects a measured outcome. If the effect size is positive, the outcome increases. If the effect size is negative, the outcome decreases. See Estimating Program Effects Using Effect Sizes for additional information.

Adjusted effect sizes are used to calculate the benefits from our benefit cost model. WSIPP may adjust effect sizes based on methodological characteristics of the study. For example, we may adjust effect sizes when a study has a weak research design or when the program developer is involved in the research. The magnitude of these adjustments varies depending on the topic area.

WSIPP may also adjust the second ES measurement. Research shows the magnitude of some effect sizes decrease over time. For those effect sizes, we estimate outcome-based adjustments which we apply between the first time ES is estimated and the second time ES is estimated. We also report the unadjusted effect size to show the effect sizes before any adjustments have been made. More details about these adjustments can be found in our Technical Documentation.

Meta-Analysis of Program Effects
Outcomes measured Treatment age No. of effect sizes Treatment N Adjusted effect sizes(ES) and standard errors(SE) used in the benefit - cost analysis Unadjusted effect size (random effects model)
First time ES is estimated Second time ES is estimated
ES SE Age ES SE Age ES p-value
34 4 238 -0.378 0.187 34 0.000 0.187 37 -0.378 0.043
34 5 250 -0.083 0.105 34 n/a n/a n/a -0.083 0.428
34 9 650 -0.150 0.064 34 0.000 0.187 37 -0.150 0.020
34 1 52 -0.392 0.201 34 0.000 0.187 37 -0.392 0.051
34 19 1024 0.156 0.071 34 n/a n/a n/a 0.156 0.035
1In addition to the outcomes measured in the meta-analysis table, WSIPP measures benefits and costs estimated from other outcomes associated with those reported in the evaluation literature. For example, empirical research demonstrates that high school graduation leads to reduced crime. These associated measures provide a more complete picture of the detailed costs and benefits of the program.

2“Others” includes benefits to people other than taxpayers and participants. Depending on the program, it could include reductions in crime victimization, the economic benefits from a more educated workforce, and the benefits from employer-paid health insurance.

3“Indirect benefits” includes estimates of the net changes in the value of a statistical life and net changes in the deadweight costs of taxation.
Detailed Monetary Benefit Estimates Per Participant
Affected outcome: Resulting benefits:1 Benefits accrue to:
Taxpayers Participants Others2 Indirect3 Total
Alcohol use disorder Criminal justice system $2 $0 $5 $1 $7
Labor market earnings associated with alcohol abuse or dependence $1,635 $3,851 $0 $0 $5,485
Property loss associated with alcohol abuse or dependence $0 $4 $8 $0 $13
Illicit drug use disorder Health care associated with illicit drug abuse or dependence $295 $46 $303 $147 $791
Mortality associated with illicit drugs $88 $207 $0 $1,598 $1,892
Program cost Adjustment for deadweight cost of program $0 $0 $0 ($157) ($157)
Totals $2,019 $4,108 $316 $1,589 $8,031
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Detailed Annual Cost Estimates Per Participant
Annual cost Year dollars Summary
Program costs $263 2014 Present value of net program costs (in 2022 dollars) ($314)
Comparison costs $0 2014 Cost range (+ or -) 10%
This program typically consists of one or two individual sessions. Our per-participant cost is the weighted average estimate of the individual and group sessions provided in the studies included in the analysis, using rates for Medicaid clients paid by Washington State for substance abuse treatment in 2014. The costs of this intervention are in addition to other treatment clients might receive.
The figures shown are estimates of the costs to implement programs in Washington. The comparison group costs reflect either no treatment or treatment as usual, depending on how effect sizes were calculated in the meta-analysis. The cost range reported above reflects potential variation or uncertainty in the cost estimate; more detail can be found in our Technical Documentation.
Benefits Minus Costs
Benefits by Perspective
Taxpayer Benefits by Source of Value
Benefits Minus Costs Over Time (Cumulative Discounted Dollars)
The graph above illustrates the estimated cumulative net benefits per-participant for the first fifty years beyond the initial investment in the program. We present these cash flows in discounted dollars. If the dollars are negative (bars below $0 line), the cumulative benefits do not outweigh the cost of the program up to that point in time. The program breaks even when the dollars reach $0. At this point, the total benefits to participants, taxpayers, and others, are equal to the cost of the program. If the dollars are above $0, the benefits of the program exceed the initial investment.

Citations Used in the Meta-Analysis

Ball, S.A., Martino, S., Nich, C., Frankforter, T.L., Van, H.D., Crits-Christoph, P., . . . Carroll, K.M. (2007). Site matters: Multisite randomized trial of motivational enhancement therapy in community drug abuse clinics. Journal of Consulting and Clinical Psychology, 75 (4), 556-567.

Blondell, R.D., Frydrych, L.M., Jaanimagi, U., Ashrafioun, L., Homish, G.G., Foschio, E.M., & Bashaw, H.L. (2011). A randomized trial of two behavioral interventions to improve outcomes following inpatient detoxification for alcohol dependence. Journal of Addictive Diseases, 30(2), 136-148.

Brown, J.M., & Miller, W.R. (1993). Impact of motivational interviewing on participation and outcome in residential alcoholism treatment. Psychology of Addictive Behaviors, 7(4), 211-218.

Carroll, K.M., Libby, B., Sheehan, J. & Hyland, N. (2001). Motivational interviewing to Enhance Treatment Initiation in Substance Abusers: An Effectiveness Study. The American Journal on Addictions, 10(4), 335-339.

Carroll, K.M., Ball, S.A., Nich, C., Martino, S., Frankforter, T.L., Farentinos, C., . . . Woody, G.E. (2006). Motivational interviewing to improve treatment engagement and outcome in individuals seeking treatment for substance abuse: A multisite effectiveness study. Drug and Alcohol Dependence, 81(3), 301-312.

Carroll, K.M., Martino, S., Ball, S.A., Nich, C., Frankforter, T., Anez, L. M., . . . Farentinos, C. (2009). A multisite randomized effectiveness trial of motivational enhancement therapy for Spanish-speaking substance users. Journal of Consulting and Clinical Psychology, 77(5), 993-999.

Daley, D.C., Salloum, I.M., Zuckoff, A., Kirisci, L., & Thase, M.E. (1998). Increasing treatment adherence among outpatients with depression and cocaine dependence: Results of a pilot study. The American Journal of Psychiatry, 155(11), 1611-1613.

Davis, T.M., Baer, J.S., Saxon, A.J., & Kivlahan, D.R. (2003). Brief motivational feedback improves post-incarceration treatment contact among veterans with substance use disorders. Drug and Alcohol Dependence, 69(2), 197-203.

Dench, S., & Bennett, G. (2000). The impact of brief motivational intervention at the start of an outpatient day programme for alcohol dependence. Behavioral and Cognitive Psychotherapy, 28(2), 121-130.

Longshore, D., & Grills, C. (2000). Motivating illegal drug use recovery: Evidence for a culturally congruent intervention. Journal of Black Psychology, 26(3), 288-301.

Lozano, B.E., LaRowe, S.D., Smith, J.P., Tuerk, P., & Roitzsch, J. (2013). Brief motivational feedback may enhance treatment entry in veterans with comorbid substance use and psychiatric disorders. The American Journal on Addictions, 22(2), 132-135.

Martino, S., Carroll, K.M., Nich, C., & Rounsaville, B.J. (2006). A randomized controlled pilot study of motivational interviewing for patients with psychotic and drug use disorders. Addiction, 101(10), 1479-1492.

Miller, W.R., Yahne, C.E., & Tonigan, J.S. (2003). Motivational interviewing in drug abuse services: a randomized trial. Journal of Consulting and Clinical Psychology, 71(4), 754-63.

Mitcheson, L., McCambridge, J., & Byrne, S. (2007). Pilot cluster-randomised trial of adjunctive motivational interviewing to reduce crack cocaine use in clients on methadone maintenance. European Addiction Research, 13(1), 6-10.

Mullins, S.M., Suarez, M., Ondersma, S.J., & Page, M.C. (2004). The impact of motivational interviewing on substance abuse treatment retention: A randomized control trial of women involved with child welfare. Journal of Substance Abuse Treatment, 27(1), 51-58.

Nyamathi, A., Shoptaw, S., Cohen, A., Greengold, B., Nyamathi, K., Marfisee, M., de, C.V., ... Leake, B. (2010). Effect of motivational interviewing on reduction of alcohol use. Drug and Alcohol Dependence, 107(1), 23-30.

Nyamathi, A.M., Nandy, K., Greengold, B., Marfisee, M., Khalilifard, F., Cohen, A., & Leake, B. (2011). Effectiveness of intervention on improvement of drug use among methadone maintained adults. Journal of Addictive Diseases, 30(1), 6-16.

Saunders, B., Wilkinson, C., & Phillips, M. (1995). The impact of a brief motivational intervention with opiate users attending a methadone programme. Addiction, 90(3), 415-424.

Winhusen, T., Kropp, F., Babcock, D., Hague, D., Erickson, S. J., Renz, C., . . . Somoza, E. (2008). Motivational enhancement therapy to improve treatment utilization and outcome in pregnant substance users. Journal of Substance Abuse Treatment, 35(2), 161-173.