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Functional Family Therapy (FFT) for court-involved youth

Juvenile Justice
Benefit-cost methods last updated December 2019.  Literature review updated March 2019.
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Functional Family Therapy (FFT) is a structured family-based intervention that uses a multi-step approach to enhance protective factors and reduce risk factors in the family. The five major components of FFT include engagement, motivation, relational assessment, behavior change, and generalization. FFT typically involves 12 to 14 therapist visits over a three- to five-month period.

Studies included in the analysis report that youth have moderate or high risk for recidivism, per a validated risk assessment tool. In the studies in our analysis that reported demographic information, 55% of FFT participants were youth of color and 26% were female. Studies in this analysis compare FFT to treatment as usual, which was typically probation with referrals to community-based services.

This analysis includes studies where FFT is provided to youth in the community following either arrest or adjudication. Evaluations of FFT where youth receive the program upon their release from confinement and FFT for youth convicted of a sex offense are excluded from this analysis and analyzed separately.

Key Terms

Court-involved youth: Youth who are processed through the juvenile justice system but who are not ordered to a period of confinement in a residential or correctional facility. This includes populations of arrested youth, diverted youth, charged youth, adjudicated youth, and youth on probation or formal supervision.

Youth in state institutions: Youth who are confined in a residential or correctional facility when they participate in the program.

Youth post-release: Youth who are returning to the community following a period of confinement in a residential or correctional facility and who participate in the program after release to the community.

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 (2018). 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 $3,374 Benefits minus costs $7,197
Participants $656 Benefit to cost ratio $2.76
Others $7,769 Chance the program will produce
Indirect ($518) benefits greater than the costs 72 %
Total benefits $11,282
Net program cost ($4,084)
Benefits minus cost $7,197

^^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
16 1 52 0.522 0.405 16 n/a n/a n/a 0.522 0.198
16 1 280 -0.075 0.078 18 n/a n/a n/a -0.075 0.339
16 4 925 -0.145 0.137 17 -0.145 0.137 25 -0.145 0.290
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
Crime Criminal justice system $3,121 $0 $7,378 $1,560 $12,060
Labor market earnings associated with high school graduation $326 $766 $424 $0 $1,516
Costs of higher education ($73) ($110) ($33) ($36) ($253)
Program cost Adjustment for deadweight cost of program $0 $0 $0 ($2,042) ($2,042)
Totals $3,374 $656 $7,769 ($518) $11,282
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Detailed Annual Cost Estimates Per Participant
Annual cost Year dollars Summary
Program costs $3,877 2016 Present value of net program costs (in 2018 dollars) ($4,084)
Comparison costs $0 2016 Cost range (+ or -) 20 %
The per-participant cost estimate is the weighted average cost of providing Functional Family Therapy (FFT), as implemented in the studies included in this analysis. We use the cost and average length of the program in Washington (3 months), provided by C. Redman (personal communication, Washington State Juvenile Rehabilitation, April 16, 2019), to estimate a monthly cost. This cost reflects estimates from Barnoski, R. (2009). Providing evidence-based programs with fidelity in Washington State juvenile courts: Cost analysis (Doc. No. 09-12-1201). Olympia: Washington State Institute for Public Policy. We multiply the monthly cost estimate and the average length of FFT in the included studies, approximately 3.4 months. The comparison group cost represents treatment-as-usual, which includes probation with referrals to community-based services and programming.
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

Barnoski, R. (2004). Outcome evaluation of Washington State's research-based programs for juvenile offenders (Document No. 04-01-1201). Olympia: Washington State Institute for Public Policy.

Darnell, A.J., & Schuler, M.S. (2015). Quasi-experimental study of Functional Family Therapy effectiveness for juvenile justice aftercare in a racially and ethnically diverse community sample. Children and Youth Services Review, 50 (3), 75-82.

Hannson, K. (1998). Functional Family Therapy replication in Sweden: Treatment outcome with juvenile delinquents. Paper presented to the Eighth International Conference on treating addictive behaviors. Santa Fe, NM, February 1998, as reported in: Alexander, J., Barton, C., Gordon, D., Grotpeter, J., Hansson, K., Harrison, R., Mears, S., Mihalic, S., Parsons, B., Pugh, C., Schulman, S., Waldron, H., and Sexton, T. (1998). Blueprints for Violence Prevention, Book Three: Functional Family Therapy. Boulder, CO: Center for the Study and Prevention of Violence.

Humayun, S., Herlitz, L., Chesnokov, M., Doolan, M., Landau, S., & Scott, S. (2017). Randomized controlled trial of Functional Family Therapy for offending and antisocial behavior in UK youth. Journal of Child Psychology and Psychiatry, 5.

Peterson, A. (2017). Functional Family Therapy in a probation setting: Outcomes for youths starting treatment January 2010 - September 2012. Olympia, WA: Center for Court Research, Administrative Office of the Courts.