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Matrix Model Intensive Outpatient Treatment Program (IOP) for stimulant use disorders

Substance Use Disorders: Treatment for Adults
Benefit-cost methods last updated December 2023.  Literature review updated May 2014.
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The Matrix Intensive Outpatient Model (Matrix Model) is a manualized, standalone outpatient program for treating individuals with stimulant use disorders. The program includes individual, group, and family sessions and covers topics including skills training, relapse prevention, drug education, social support, and self-help groups. Treatment generally lasts four to six months and includes multiple individual and group sessions per week.
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 $885 Benefits minus costs $2,825
Participants $1,105 Benefit to cost ratio $2.87
Others $458 Chance the program will produce
Indirect $1,885 benefits greater than the costs 52%
Total benefits $4,333
Net program cost ($1,508)
Benefits minus cost $2,825

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

^^WSIPP does not include this outcome when conducting benefit-cost analysis for this program.

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 1 137 0.060 0.241 34 0.000 0.187 37 0.060 0.803
34 1 59 -0.146 0.382 34 n/a n/a n/a -0.146 0.703
34 4 342 -0.235 0.156 34 0.000 0.187 37 -0.235 0.132
34 1 59 -0.071 0.457 34 n/a n/a n/a -0.071 0.877
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 Labor market earnings associated with alcohol abuse or dependence ($132) ($312) $0 $0 ($444)
Health care associated with alcohol abuse or dependence ($3) $0 ($3) ($1) ($7)
Property loss associated with alcohol abuse or dependence $0 $0 ($1) $0 ($1)
Mortality associated with alcohol $0 $0 $0 ($3) ($3)
Illicit drug use disorder Criminal justice system $1 $0 $3 $0 $4
Labor market earnings associated with illicit drug abuse or dependence $439 $1,035 $0 $0 $1,475
Health care associated with illicit drug abuse or dependence $447 $69 $459 $223 $1,198
Mortality associated with illicit drugs $133 $314 $0 $2,419 $2,866
Program cost Adjustment for deadweight cost of program $0 $0 $0 ($754) ($754)
Totals $885 $1,105 $458 $1,885 $4,333
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Detailed Annual Cost Estimates Per Participant
Annual cost Year dollars Summary
Program costs $2,602 2013 Present value of net program costs (in 2022 dollars) ($1,508)
Comparison costs $1,358 2013 Cost range (+ or -) 20%
Matrix Model treatment is typically provided for four to six months. The per-participant cost estimate of treatment is the weighted average of the individual and group therapy sessions provided in the studies included in the analysis. We calculated this average cost using Washington's Medicaid hourly reimbursement rate for outpatient individual and group therapy multiplied by the weighted average of the total hours of these therapies across the studies (averaging 80 total hours). Comparison group costs are computed in a similar manner based on treatment received in the studies (standard intensive outpatient treatment, standard group therapy, or no treatment).
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

Rawson, R.A., Obert, J.L., McCann, M.J., & Mann, A.J. (1985). Cocaine Treatment Outcome: Cocaine Use Following Inpatient, Outpatient, and No Treatment. NIDA Research Monograph, 67, 271-277.

Rawson, R.A., Shoptaw, S.J., Obert, J.L., McCann, M.J., Hasson, A., & Marinelli-Casey, P.J. (1995). An Intensive Outpatient Approach for Cocaine Abuse Treatment: The Matrix Model. Journal of Substance Abuse Treatment, 12(2), 117-127.

Rawson, R.A., Marinelli-Casey, P., Anglin, M.D., Dickow, A., Frazier, Y., Gallagher, C., et al. (2004). A Multi-Site Comparison of Psychosocial Approaches for the Treatment of Methamphetamine Dependence. Addiction, 99(6), 708-717.

Rosenblum, A., Magura, S., Palij, M., Foote, J., Handelsman, L., & Stimmel, B. (1999). Enhanced treatment outcomes for cocaine-using methadone patients. Drug and Alcohol Dependence, 54(3), 207-218.