Homeless adolescents and young adults are considered one of the most vulnerable populations worldwide with an estimated 100 million globally and 500,000 to 2.8 million in the US alone. A multitude of studies document high rates of alcohol and drug use, sexual risk behaviors, and physical and mental health vulnerabilities (Robertson & Toro, 1999). Homeless adolescents and young adults frequently report histories of childhood physical and/or sexual abuse (Robertson & Toro, 1999) and are disconnected from family, housing, and social services (Gaetz, 2004). The purpose of this study was to identify the most effective intervention for addressing substance use, as well as secondary outcomes including housing, mental health problems, and victimization among three theoretically distinct but empirically supported interventions: the community reinforcement approach (CRA; Meyers & Smith, 1995), motivational enhancement therapy (MET; Miller & Rollnick, 2012), and case management (CM).
Substance use disorders are common among homeless adolescents and young adults, with studies estimating that 69 to 86 percent meet diagnostic criteria for at least one substance use disorder (Baer, Ginzler, & Peterson, 2003). In addition to the direct negative effects of substance use, there are significant social, legal, and physical health consequences (Edidin, Ganim, Hunter, & Karnik, 2012). For example, substance use is associated with other mental health disorders and increases adolescents’ and young adults’ risk of victimization on the streets (Greene, Ennett, & Ringwalt, 1997). Substance use can inhibit one’s exit from homelessness and increases the potential for chronic homelessness into adulthood (Greene et al., 1997; Robertson & Toro, 1999). Overall, treatment for substance use disorders is a priority when intervening with homeless adolescents and young adults, not only because of the high prevalence of substance use disorders in this population, but also because of the multitude of negative consequences associated with it.
Furthermore, the problems experienced by homeless youth are interrelated, and the treatment of substance use problems has been associated with improvements in other affected domains including depressive symptoms, internalizing and externalizing problems, and coping and victimization experiences (Slesnick, Prestopnik, Meyers, & Glassman, 2007). Despite the challenges experienced by these youth, current research offers limited guidance regarding how to intervene and treat this population (Edidin et al., 2012; Robertson & Toro, 1999). Homeless youth present with challenges not faced by those who are not experiencing homelessness. In particular, they are less connected to familial, institutional or other supports, and rarely enter substance use treatment on a voluntary basis, though they can be engaged in treatment through outreach (Fisk, Rakfeldt, & McCormack, 2006). Because of the range of difficulties, providing substance use treatment for people who are homeless cannot be separated from the larger needs for assistance with housing, employment, and income. For example, recovery outcomes can be enhanced, and social isolation diminished, through the use of advocates who assertively link persons who are homeless to community-based support programs (National Alliance to End Homelessness, 2006).
Recent reviews of the adolescent substance use treatment literature identify several effective individual, group, and family interventions (Tanner-Smith, Wilson, & Lipsey, 2013; Waldron & Turner, 2008). Some evidence suggests that family therapy interventions outperform other interventions, but more research supporting this conclusion is needed. Given the range of available effective treatment options, researchers suggest that cost effectiveness (Tanner-Smith et al., 2013) and response to treatment (Waldron & Turner, 2008) should be considered when selecting a treatment. However, as noted, very few intervention studies have been conducted with homeless youth, and those few studies targeted a wide range of outcomes using various interventions. In two recent literature reviews, Altena and colleagues (2010) identified eleven intervention studies while Slesnick and colleagues (2009) identified fourteen studies. These few studies tested individual, family, group, and street-based interventions focused on substance use, mental health, sexual and HIV risk, and employment.
Identifying effective interventions is also complicated by the fact that subgroups of runaway and homeless adolescents and young adults exist, with different intervention needs among them (Chamberlain & MacKenzie, 2004; Haber & Toro, 2004). That is, presence on the streets is considered a marker of problem severity. Shelter-recruited adolescents tend to be younger, and often have never spent a night on the streets (Robertson & Toro, 1999). Family reunification is the primary goal of runaway shelters, with family therapy a recommended approach (Slesnick, Dashora, Letcher, Erdem, & Serovich, 2009; Teare et al., 1994). In contrast, street-living homeless adolescents and young adults rarely access institutional settings—shelters, foster care—or family for assistance because these systems are no longer perceived to meet their needs (Marshall & Bhugra, 1996). Community-based interventions offered in low-demand settings such as drop-in centers are recommended for street-living adolescents and young adults (Chamberlain & MacKenzie, 2004). Drop-in centers offer youth a bridge from the streets to the mainstream, with few requirements placed upon youth. These centers usually address basic needs and seek to connect youth to more intensive services as trust develops. Promising interventions for street-living adolescents and young adults include case management, brief motivational interviewing, and behavioral interventions (Altena, Brilleslijper-Kater, & Wolf, 2010; Slesnick et al., 2009). Information on the relative performance of these promising interventions can offer evidence supporting intervention options for those seeking to serve this population.
Current Study
The current study compared treatment outcomes for homeless youth evidencing substance use disorder assigned to CM, CRA or MET provided through a local drop-in center. It was hypothesized that adolescents and young adults receiving each treatment would show significant improvements in the primary outcome, alcohol and drug use, as well as the secondary outcomes including depressive symptoms, internalizing/externalizing problems, victimization, homelessness, and coping from baseline to the twelve-month follow-up. Though comparison to services as usual would have been a reasonable control condition, since CRA already showed superior outcomes to services as usual, the question of interest was how CRA would compare to other promising interventions. Overall, it was expected that those receiving CRA would exhibit more improvements in all outcome variables than the other two treatments during the twelve-month period. In addition, research suggests that substance use outcomes may be moderated by age, sex, ethnicity, and a history of childhood abuse (Greenfield et al., 2007; Slesnick, Erdem, Bartle-Haring, & Brigham, 2013), and these moderators were tested in the current study. Differences between CRA and the other two treatments on the outcomes of interest were expected to be particularly pronounced for older youth, females, whites, and youth without a history of child abuse.
Methods
Participants
Homeless adolescents and young adults (n = 270) were recruited from the only drop-in center serving homeless adolescents and young adults in Central Ohio. Eligible participants met the criteria of homelessness as defined by the McKinney-Vento Act (2002) as those who lack a fixed, regular, and adequate nighttime residence; lives in a welfare hotel, or place without regular sleeping accommodations; or lives in a shared residence with other persons due to the loss of one’s housing or economic hardship. Of those approached for participation in the study, 34 percent were eligible and 75 percent of those agreed to participate. Eligible participants were recruited between October 2006 to December 2009, were between the ages of fourteen to twenty years, and met Diagnostic and Statistical Manual for Mental Disorders, fourth edition, (DSM-IV; APA, 2000) for abuse or dependence for psychoactive substance use or alcohol disorder, as assessed by the computerized diagnostic interview schedule (CDIS; Shaffer, 1992). All but four participants—one fourteen-year-old and three fifteen-year-olds—were between the ages of sixteen and twenty years.
Procedure
A research assistant (RA) engaged and screened homeless youth at the drop-in center to determine basic eligibility for the study. After determining eligibility and interest, written informed consent was obtained from young adults who were eighteen years or older and assent was obtained for youth under eighteen years prior to beginning the assessment battery. Following the baseline assessment, a computerized randomization program was used to assign participants to CRA (n = 93, 34.44 percent), MET (n = 86, 31.85 percent) or CM (n = 91, 33.70 percent). MET included two one-hour sessions, while CRA and CM had twelve one-hour sessions. Each intervention condition also included two one-hour HIV prevention sessions. Therefore, the total number of sessions was four for MET, and fourteen for CRA and CM. All sessions were completed within six months of the baseline assessment interview. In each condition, therapists and case managers were available twenty-four hours for crises. Follow-up assessments were conducted at three, six, and twelve months postbaseline. Participants were reimbursed with a $25 gift card at completion of the baseline assessment battery, a $50 gift card for at each follow-up assessment, and a $5 gift card for each session attended. All research procedures were approved by the Institutional Review Board at The Ohio State University.
Treatment Conditions
CRA is an operant-based therapy with the goal to help individuals restructure their environment so that drug use or other maladaptive behaviors are no longer reinforced and other positive behaviors are reinforced. CRA treatment procedures are detailed in a book written by the developers (Meyers & Smith, 1995). Therapists follow a standard set of core procedures and a menu of optional treatment modules matched to clients’ needs (Meyers & Smith, 1995). The core session topics include:
- A functional analysis of using behaviors
- Refusal skills training
- Relapse prevention
- Job skills
- Social skills training, including communication and problem-solving skills
- Social and recreational counseling
- Anger management and affect regulation
Each area of focus is determined based upon the goals of counseling, and intervention components are repeated until the participant and therapist agree that the goal has been achieved. Additional optional modules are included based upon each clients’ needs and strengths. Because the intervention is tailored to the unique needs and environmental context of individual clients, it is easily adapted to the multiple and various circumstances of those experiencing homelessness (e.g., limited recreational/social reinforcers).
MI assumes that the responsibility and capability for change lie within clients, and need to be evoked, rather than created or instilled (Miller & Rollnick, 2013). Four principles guide the practice of MI: express accurate empathy, develop discrepancy, roll with resistance, and support self-efficacy. An adaptation of MI that has been well-tested, both with adults and with adolescents, is motivational enhancement therapy (MET), which includes feedback. Session one begins with open-ended MI, to establish therapeutic rapport and elicit client’ change talk in regards to their substance use. Next, clients are given specific feedback about their substance use from the baseline assessment, within an MI counseling style. This period of feedback often continues into session two. The therapist continues to focus on enhancing intrinsic motivation for change, transitioning as appropriate into the negotiation of a change plan, and evoking commitment to the plan. Sessions one and two directly paralleled sessions one and two of the MET manual developed for Project MATCH (Miller, Zweben, DiClemente, & Rychtarik, 1999).
Using a strengths-based CM model (Rapp et al., 2008), case managers seek to link participants to resources within the community. The initial case management meeting provides an opportunity to gather information. The case manager reviews each of six general areas with participants to gather a history and picture of the current situation:
- Housing needs
- Health/mental health care, including alcohol/drug use intervention
- Food
- Legal issues
- Employment
- Education
Consistent with a strengths-based CM approach, the case manager takes responsibility for securing needed services for the youth and remains a support for the youth as he/she traverses the system of care. The strengths-based approach also includes the following features: dual focus on client and environment, use of paraprofessional personnel, a focus on clients’ strengths rather than deficits, and a high degree of responsibility given to clients in directing and influencing the intervention that they receives from the system and the outreach worker. Once this review is complete, an initial intervention plan is developed with specific goals and objectives. A manual and goal development sheets were developed by the first author. Service is not restricted to the office and includes transportation of clients to appointments, interviews, and related activities.
Analytic Strategies
This study used an intent to treat (ITT) design which consisted of the entire sample of 270 participants. Outcomes for the treated sample were also examined, and consisted of 188 participants who attended 25 percent or more of the total possible treatment sessions (four for CRA and CM, one for MET). Also, clinical significance of the pre-to-post changes was analyzed for all outcome variables. Clinical significance, as separate from statistical significance, is defined as the extent to which therapy moves someone outside the range of the dysfunctional population (Jacobson, Follette, & Revenstorf, 1984).
Clinical Implications
Adding to a very small number of studies, the current study offers findings from a comparative effectiveness trial of three empirically supported interventions for homeless adolescents and young adults evidencing substance use disorder. Each intervention has shown efficacy in treating substance use problems and for those experiencing homelessness. Of interest in this study was whether differential support would be found for CRA, previously found to show significant improvements in multiple domains compared to drop-in center services alone (Slesnick et al., 2007). Treatment providers want to know which treatment is most effective for use with this population, and this study offers some preliminary conclusions.
Primary Outcome
Participants in all three interventions exhibited decreasing trends in the average frequency of alcohol or drug use and average SECs. In regard to frequency of alcohol and drug use, the ITT analysis showed no differences among the three treatments, with all showing statistically significant reductions to twelve months. Even though CM did not target substance use directly, it performed similarly to the two other evidence-based, manualized treatment models. This finding supports the continued use of CM by drop-in centers, and implies that drop-in centers may not need to transition to new, and potentially more expensive, intervention models. However, at least in the treated sample, CRA showed a significantly greater reduction in drug use frequency compared to CM. Therefore, in the treated sample, the findings suggest that a targeted substance use treatment (CRA) is more effective. It should be noted that although reductions in the primary outcomes were statically significant in all three interventions, at the twelve-month follow-up assessment, the average frequency of drug use was still high, with participants reporting using illicit drugs on 40 percent to 50 percent of the prior ninety days. It may be the case that improvements in substance use without housing are limited. Therefore, the current findings suggest that these three treatments have significant harm reduction potential.
Of potentially greatest significance to the field, the current findings offer evidence indicating that homeless youth, who were not seeking treatment for substance use disorders, and for whom the program did not provide housing, can be successfully engaged into treatment and have successful outcomes, with between 54 to 59 percent of the sample showing clinically significant improvement across time on most outcomes. Unlike the findings of Baer et al. (2007), this study indicates that those assigned to MET showed significantly reduced alcohol and drug use even to twelve months postbaseline, findings similar to those with younger adolescents residing in a runaway shelter (Slesnick, Erdem, Bartle-Haring, & Brigham, 2013). Also, these findings support the use of case management as a stand-alone intervention, as found by Wagner et al. (1994). Overall, the findings in this study showing significant improvements over time, but few differences between conditions, mirror those with the more stable adolescents recruited from a runaway shelter (Slesnick et al., 2013) as well as housed adolescents (Dennis et al., 2004; Godley et al. 2010).
Secondary Outcome
Significant reductions in depressive symptoms and homelessness were observed in all three intervention conditions. A few differences were found between interventions on other secondary outcomes. While no intervention condition exhibited significant improvements in task- or emotion-oriented coping, those assigned to MET improved significantly in avoidance-oriented coping. Also, only those who were assigned to CM showed significant decreases in internalizing and externalizing behaviors. CM helped youth manage their lives, likely reducing stress and leading to the observed improvements in mental health and other outcomes. Significant decreases in victimization experiences were also found among those in the CM and CRA condition, but not MET.
Moderators
Compared to males, females showed a greater reduction in alcohol and drug use frequency, converging with other studies indicating that females are more likely than males to show better alcohol and drug use outcomes (Greenfield et al., 2007; Slesnick, Erdem, Collins, Bantchevska, & Katafiasz, 2011). In addition, this study showed that a history of childhood physical abuse—but not sexual abuse—was associated with poorer drug use and homelessness outcomes. Possibly, those with histories of physical abuse also experience negative sequaelae associated with physical trauma such as traumatic brain injury and/or other comorbid conditions, which have also been shown to negatively impact treatment outcomes. Finally, confirming findings from previous studies showing that childhood victimization predicts greater victimization on the streets (Robertson & Toro, 1999), fewer reductions in street victimization were observed among those who experienced childhood physical and sexual abuse.
Limitations
This research is limited in that all adolescents and young adults were recruited as a sample of convenience, and in one city, from the only drop-in center in central Ohio. Cities vary in racial/ethnic distribution and substance use patterns (Edidin et al., 2012) and the participants recruited in this study might not be representative of those from other parts of the country. While participants were provided a $5 food gift card for each session attended in this study, drop-in centers could offer other food items to encourage treatment attendance, such as choice of a selection of food items, usually obtained through food banks. On average, participants attended about half of the available sessions, likely due to their chaotic lifestyles. But, in fact, we consider it a success to have engaged these youth in multiple treatment sessions, especially since they were homeless and were not originally seeking treatment for substance use disorders. The session completion rates reported here are similar to other adolescent substance use treatment studies with more stable, housed youth, with Godley et al. (2014) reporting that 68 percent of adolescents completed four or more CM sessions (out of twelve sessions total) versus an average of 7.3 sessions and 64 percent in this sample completing four or more sessions.
Conclusions and Future Directions
This is the second randomized clinical trial indicating that substance use treatment, specifically CRA, is effective with street living homeless adolescents and young adults. The first trial indicated that CRA was superior to treatment as usual (TAU) or standard drop-in services (Slesnick et al., 2007). As such, the current trial did not include a TAU condition, and all interventions were considered viable intervention options (Carroll & Rounsaville, 2003). Although some evidence was found for CRA to have superior drug use outcomes in the treated sample, no other differences between the three interventions were observed and evidence for the superiority or inferiority of interventions was not provided. Drop-in centers have a unique opportunity to engage homeless adolescents and young adults into more intensive treatments including substance use treatment. Providing access to treatment within the drop-in center is likely more effective than referring clients to other treatment programs. That is, drop-in centers are typically considered a bridge between the streets and the mainstream, and are low-demand settings. Many young people experiencing homelessness have had negative experiences with family, school, and typical services within systems meant to serve them, such as shelters or foster care. This population is considered difficult to engage and to serve given low levels of trust, transportation, and stability. Those who do not want treatment or intervention cannot be called or visited at their home, and accessing other programs is complicated by lack of insurance and transportation. Anecdotally, successful treatment requires the development of a trusting relationship which may be key to further change. In summary, this study adds to a very small body of literature seeking to identify effective interventions for treating homeless youth evidencing substance use disorder. The findings suggest that drop-in centers have a choice of efficacious interventions when serving this group, though given fewer sessions, MET may be a more cost-effective option (Dennis et al., 2004).
Acknowledgements: This research was supported by NIDA grant R01 DA13549 to the first author.
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Editor’s Note: This article was adapted from an article by the same authors previously published in the Journal of Substance Abuse Treatment (JSAT). This article has been adapted as part of Counselor’s memorandum of agreement with JSAT. The following citation provides the original source of the article:
Slesnick, N., Guo, X., Brakenhoff, B., & Bantchevska, D. (2015). A comparison of three interventions for homeless youth evidencing substance use disorders: Results of a randomized clinical trial. Journal of Substance Abuse Treatment, 54, 1–13.