Comparative Effectiveness of Residential Versus Outpatient Treatments for Adolescents with Substance Use Problems: A Quasiexperimental Study

Background and Purpose: Level of care placement is an essential component of substance abuse treatment. Often before an intervention is chosen, there is a decision about whether a client needs residential or outpatient treatment. However, very little research has been conducted with adolescents with substance use problems to determine under what circumstances higher levels of care produce better outcomes.  This large scale quasi-experimental study compares the 12-month outcomes of adolescents who received either outpatient or residential treatments.  Based on previous research that compared adults treated in different levels of care, we hypothesized that there would be no differences between those adolescents treated in residential and matched controls treated in outpatient settings. 

Methods: A subset of participants were selected from 16,491 adolescents who had been treated at SAMHSA-funded agencies from 1998 to 2008. Initially, 5320 outpatient adolescents and 1641 adolescents treated in residential settings (out of 16491) met our study’s inclusion criteria.  These criteria included having valid 12 month follow-up data available for analysis and not having received residential treatment during the 90 days prior to intake into this study. Using a one-to-one propensity score matching algorithm in STATA, 1195 residential adolescents were matched to 1195 outpatient adolescents based on 39 baseline matching variables such as demographic characteristics, as well as indices of substance use and mental health problem severity, treatment motivation, and criminal justice involvement.   After the matching, significant differences remained on six of the 39 matching variables, but differences were small (i.e., effect sizes less than 0.12). After matching we used level of care to predict 12-month follow-up outcomes, including: abstinence while residing in the community (i.e., recovery), substance use problems, illegal activity and emotional problems. We controlled for the confounding variables that remained significantly different after matching. 

Results: As hypothesized,there were no significant differences between the residential and outpatient groups on abstinence in the community (p=0.8) and substance use problems (p=0.9) at follow-up . However, the outpatient group reported significantly fewer illegal activities (p<0.0001) and emotional problems (p<0.0001) at 12-month follow-up.

Implications: For adolescents who were matched at baseline, the long-term impact of residential and outpatient treatment was equivalent on recovery and substance use problems outcomes. However, the outpatient group fared better on illegal behavior and emotional problem outcomes.  These results have important practice implications. First, it appears that we are overtreating some youth who will likely derive equivalent or superior benefits when treated in less restrictive environments. It is unclear what impact this has on youth assigned to higher than needed levels of care.  However, it is likely that we would achieve high cost savings by refining placement criteria and reserving residential treatments for only the most severe youth.  We note that our study was limited by the inability to match the most severe residential clients (27%) in this sample to comparable outpatient controls, which limits the generalizability to adolescents with less severity.   Further study is needed to test whether youth with such serious problems would respond equally well to community-based treatments.