The methodological architecture of the review is worth examining because it shapes what the conclusions can and cannot tell us. A systematized review, as the authors define it following the typology of Grant and Booth, applies systematic review principles—structured searches, explicit inclusion criteria, and standardized data extraction—without necessarily the full protocol registration and dual independent review apparatus of a gold-standard systematic review. The team searched across four conceptual domains: young adulthood, interventions, substance use, and traumatic stress, with homelessness terms added and removed to capture both directly relevant studies and the wider evidence base from which adaptable elements might be borrowed. Data were extracted using a structured coding framework organized around three domains: effectiveness, real-world implementation, and intervention characteristics. This tripartite structure reflects a growing recognition in implementation science that an intervention’s clinical efficacy in a controlled trial tells only part of the story; whether it can actually be delivered, sustained, and funded in a community drop-in center or shelter is a separate and equally consequential question.

On the effectiveness front, the headline numbers are encouraging. Over half of the 39 included studies used randomized controlled designs, the most rigorous method for establishing causal effects, and roughly three-quarters reported significant improvements across multiple outcomes, including reductions in substance use, decreases in traumatic stress symptoms, and broader gains in mental health. That such a large proportion of interventions produced measurable benefits suggests the field is not starting from zero. Yet the review’s finer-grained analysis reveals why these findings cannot simply be transplanted to young adults experiencing homelessness. The interventions were most commonly delivered in academic, clinical, or service settings—university counseling centers, primary care clinics, structured research programs—with enormous variation in duration, treatment modality, and theoretical orientation. A web-based alcohol prevention program for college students, a telephone-based intervention for heavy drinking in primary care, a family-based group intervention for HIV and drug risk among homeless families, and home-based telehealth skills training for women veterans all appeared in the evidence base, each built around assumptions about stability, scheduling, and access that homeless young adults often cannot meet.

The co-occurrence problem sits at the heart of the review’s rationale. Epidemiological research has long documented that trauma and substance use are deeply intertwined in this population. Studies cited by the authors, including work by Bender and colleagues on homeless youth in three U.S. cities and by Gwadz and colleagues on gender differences in traumatic events among homeless youth, show elevated rates of posttraumatic stress disorder and multiple victimization both before and after young people leave home. The self-medication hypothesis, articulated by Khantzian, offers one explanatory framework: substances are used to blunt the intrusive memories, hyperarousal, and emotional dysregulation that follow traumatic exposure. Trauma itself is increasingly understood as a transdiagnostic risk factor, elevating risk across a range of mental disorders, and homelessness compounds the problem by exposing young adults to ongoing victimization and instability that perpetuate both the traumatic stress and the substance use. The result is a cycle in which each element exacerbates the others, prolonging homelessness and degrading health outcomes. Yet the review found that interventions addressing both traumatic stress and substance use simultaneously were rare, and none had been built from the ground up for young adults experiencing homelessness.

The implementation findings are particularly revealing about the gap between what works in trials and what survives contact with real-world service systems. The review found strong participant retention across many studies, which is notable given that retention is often the Achilles heel of interventions with mobile, crisis-exposed populations. However, reporting on treatment fidelity—whether the intervention was actually delivered as designed—and on cost was strikingly limited. Fidelity monitoring matters because an intervention that shows effects in a tightly supervised trial may drift or degrade when handed to frontline staff with competing demands; without fidelity data, implementers cannot know which results are reproducible. Cost reporting matters because service agencies operating on thin budgets must make allocation decisions, and an intervention whose resource requirements are unknown cannot be planned for. These reporting gaps, the authors suggest, represent a critical blind spot for anyone hoping to move from the literature to practice.

Among the 39 studies, 16 included samples in which at least half of the participants experienced homelessness or housing instability, and these studies offer the closest available approximations to the target population. They include trials of strength-based outreach interventions linked to shelters or drop-in centers that reduced hard drug use among homeless youth, a randomized controlled trial of a smartphone application plus brief motivational intervention that reduced substance use and sexual risk behaviors among homeless young adults, a brief motivational interviewing-based group intervention showing 24-month effects on alcohol use among emerging adults experiencing homelessness, and a feasibility study of the HOME program combining housing with opioid use disorder prevention. Other work examined housing and supportive services for young mothers experiencing homelessness and intensive addiction and housing case management for homeless veterans. Collectively, these studies demonstrate that young adults experiencing homelessness can be recruited, retained, and helped—but each addressed only part of the problem, typically substance use alone, without an integrated traumatic stress component.

From this mosaic, the review distills a set of design principles for a future integrated intervention. First, delivery should be brief and flexible: long, multi-session protocols that assume reliable attendance are poorly matched to a population whose daily lives are governed by shelter curfews, survival needs, and sudden displacement. Second, harm-reduction approaches should anchor the substance use component. Rather than demanding immediate abstinence as a condition of care, harm reduction meets young people where they are, reducing the risks of use while building trust and engagement—a stance with particular resonance for a population that has often experienced rejection and coercion from institutions. Third, the intervention must be feasible within community-based service settings such as drop-in centers and shelters, which are where homeless young adults already present, rather than requiring referral into academic clinics that many will never reach. The authors frame these components as hypotheses to be tested, not a finished blueprint, and they are explicit that the review is a critical pre-implementation step in a longer development process.

The review also surfaces structural features of the existing literature that constrain its usefulness. The theoretical orientations of included interventions ranged widely, from motivational interviewing and cognitive behavioral approaches to transdiagnostic protocols such as the Unified Protocol, which targets emotional disorders broadly rather than any single diagnosis. Duration varied from single-session brief interventions to multi-month programs. Delivery modalities spanned in-person individual and group formats, family-based sessions, telephone contact, web-based programs, and smartphone applications. This heterogeneity, while a barrier to simple meta-analytic conclusions, is arguably an asset for intervention development: it provides a menu of tested mechanisms and delivery channels from which adaptable elements can be selected and recombined. The authors’ structured coding framework makes that menu explicit, which is precisely what a design team needs when assembling a new intervention rather than evaluating an old one.

What comes next, according to the authors, is direct testing within the population itself. Future research should prioritize intervention trials conducted with young adults experiencing homelessness, to determine which components retain their effectiveness and feasibility when the assumptions of stability and access no longer hold. The stakes are considerable. Homelessness among young adults is associated with elevated rates of mental health and substance use disorders, disrupted education, and long-term trajectories of instability, and the window of emerging adulthood is a developmental period in which effective intervention may alter lifelong outcomes. By systematically cataloguing what has been tried, what worked, how it was delivered, and where the evidence runs out, this review converts a scattered literature into a usable map. It does not offer a cure, and it is candid that none exists yet for this population. What it offers instead is something the field has lacked: a rigorous, transparent account of the raw materials available for building the first integrated traumatic stress and substance use intervention designed specifically for young adults experiencing homelessness, and a clear-eyed statement of the implementation conditions any such intervention must survive.

Subject of Research: Traumatic stress and substance use interventions for young adults experiencing homelessness

Article Title: A Systematized Review of Traumatic Stress and Substance Use Interventions in Young Adults: Implications for Intervention Development with Young Adults Experiencing Homelessness

Article References: Gamoran, J., Bushnell, A., Fragkos, E., Darbro, R., Gueye, A., & Snow-Hill, N. L. (2026). A Systematized Review of Traumatic Stress and Substance Use Interventions in Young Adults: Implications for Intervention Development with Young Adults Experiencing Homelessness. Community Mental Health Journal. https://doi.org/10.1007/s10597-026-01734-2

Image Credits: AI Generated

DOI: 10.1007/s10597-026-01734-2

Keywords: homelessness, young adults, traumatic stress, substance use, systematized review, intervention development, harm reduction, mental health, implementation science, PTSD, motivational interviewing, community-based services

The research team, led by Gloria Aidoo-Frimpong of the University at Buffalo in collaboration with Ghanaian colleagues from institutions including Ensign Global University and hospitals in Osiem and Offinso, brought together ten adolescent girls and young women and five community interest-holders for an intensive co-creation workshop. The methodological architecture of the study reflected a deliberate commitment to participatory design. Rather than extracting survey responses and departing, the investigators audio-recorded group discussions, captured facilitator field notes, and employed the Nominal Group Technique, a structured consensus method in which participants independently generate and rank ideas before the group deliberates. This ranking procedure allowed the researchers to quantify which barriers participants considered most pressing, while the open discussions and intervention prototypes revealed the texture and reasoning behind those priorities. Transcripts were then subjected to thematic analysis with iterative coding and consensus refinement, a process in which coders repeatedly revisited the data until the interpretive categories stabilized.

What emerged from the analysis was a four-tier map of obstacles operating at distinct but interlocking levels. The first and arguably most pervasive domain involved cultural and religious norms that moralized female sexuality. Participants described how conversations about HIV prevention were frequently framed as evidence of inappropriate behavior, so that a young woman seeking an HIV test or requesting PrEP risked being read as sexually active, and therefore as transgressing expectations of feminine propriety. This moral framing transformed a straightforward health behavior into a social gamble. The second domain concerned knowledge that was real but not actionable. Many participants had heard of HIV self-testing and PrEP, yet they lacked procedural clarity about how the tests worked, how PrEP should be taken, and what to do with a result, leaving them uncertain at precisely the moments when confidence mattered most.

The third barrier domain was emotional and relational. Fear and stigma did not operate only through overt discrimination; they worked through anticipatory distress, the dread of what might happen if a test were discovered, and through relational scrutiny, the sense that partners, family members, or neighbors were constantly evaluating a young woman’s choices. Confidentiality concerns compounded this anxiety, because participants worried that clinic staff or visible service points could expose their prevention activities to their communities. The fourth domain was structural: inconsistent availability of services meant that even motivated women could not count on finding supplies, financial barriers put testing kits and clinic visits out of reach for some, geographic inequities concentrated resources in places easier for urban than rural women to access, and health system practices themselves sometimes deterred rather than welcomed young clients.

The analytical insight of the study lies in how these domains interact. A young woman might possess accurate knowledge about PrEP, for example, but cultural norms that moralize female sexuality could make it socially costly to visit a clinic, while financial constraints and unreliable stock could render the trip futile even if she overcame her hesitation. Conversely, a well-stocked facility in her neighborhood would not help if she feared being seen entering it. The researchers mapped each barrier to the level at which it manifested, individual, interpersonal, socio-cultural, or structural, and then aligned the co-created strategies to those manifestations. This multilevel mapping matters for implementation science because interventions that address only one layer tend to be overwhelmed by the others. A peer education program, however well designed, will struggle if the nearest clinic has no PrEP in stock or if faith leaders publicly condemn its use.

The strategies that participants designed were strikingly concrete and culturally embedded. Storytelling emerged as a central vehicle: narratives grounded in local experience could carry prevention information in forms that felt legitimate rather than clinical, allowing sensitive topics to be discussed without triggering the moral judgments that direct messaging provoked. Participants also proposed deliberate engagement with faith leaders, recognizing that religious authorities shape the very norms that moralize female sexuality, and that their endorsement could either unlock or foreclose community acceptance of HIV prevention services. Rather than treating religion as an obstacle to be circumvented, the young women positioned faith communities as potential allies whose involvement could reframe prevention as responsible and respectable behavior.

Digital tools featured prominently in the co-designed package, but with an attention to developmental nuance that top-down programs often miss. Participants envisioned peer-led education delivered through WhatsApp, the messaging platform that dominates social communication in Ghana, with content tailored to different stages of adolescence and young adulthood. The rationale was that a fourteen-year-old girl navigating school and family supervision has different prevention needs, relationship contexts, and communication preferences than a twenty-two-year-old woman in a partnership or running her own household. A single undifferentiated message, the participants argued, would speak to neither. Alongside the peer-led channels, they proposed anonymous digital support mechanisms that would allow young women to ask questions and seek reassurance without revealing their identities, directly targeting the confidentiality fears that the analysis had identified as a core barrier.

The final strand of the co-designed strategy addressed the structural layer through decentralized, community-based service delivery. By moving HIV self-testing kits and PrEP access out of centralized facilities and into community settings, the participants aimed to reduce the geographic and financial costs of prevention while shrinking the visibility that made clinic visits socially risky. The emphasis on decentralization reflects a broader recognition in health services research that access is not merely a matter of distance but of the total burden, in time, money, and social exposure, that a service imposes on its user. For young women whose mobility and spending money may be controlled by others, a service that requires a long, conspicuous journey is effectively unavailable regardless of its official existence.

The WISE WOMAN findings now set the stage for a pilot phase intended to evaluate the feasibility and acceptability of the co-created strategies and to refine them for broader scale-up. The study’s authors emphasize that grounding intervention design in lived experience and structural reality offers contextually specific guidance that imported models cannot supply, and the ethical architecture of the work, approved by the University at Buffalo’s Institutional Review Board and Ensign Global College’s ethics committee and conducted in accordance with the Declaration of Helsinki and Ghana’s Data Protection Act, underscores the care taken with a vulnerable population. The research was funded through the University at Buffalo’s global research seed funding program, with the funders having no role in the design or interpretation. Whether storytelling circles, faith-leader partnerships, WhatsApp peer networks, and community distribution points can measurably raise testing and PrEP uptake remains to be demonstrated, but the study makes a compelling methodological claim: the young women closest to the problem are also the most precise diagnosticians of it, and interventions that begin with their analysis stand a far better chance of surviving contact with the communities they aim to serve.

Subject of Research: Women-centered co-design of HIV self-testing and PrEP implementation strategies for adolescent girls and young women in Ghana

Article Title: Co-developing women-centered strategies to improve HIV self-testing and PrEP uptake among adolescent girls and young women in Ghana: Findings from the WISE WOMAN study

Article References: Aidoo-Frimpong, G., Mensah, W. K., Anyidoho, D. S., Obeng, Y. A., Abubakar, A. T., & Oduro, M. A. (2026). Co-developing women-centered strategies to improve HIV self-testing and PrEP uptake among adolescent girls and young women in Ghana: Findings from the WISE WOMAN study. BMC Health Services Research. https://doi.org/10.1186/s12913-026-15750-1

Image Credits: AI Generated

DOI: 10.1186/s12913-026-15750-1

Keywords: HIV self-testing, PrEP, adolescent girls and young women, Ghana, participatory research, implementation science, human-centered design, nominal group technique, HIV stigma, women's health, community-based services, sub-Saharan Africa