Psychosocial Interventions for Newly Arrived Adolescent Refugees: A Systematic Review

Adolescent refugees are confronted with multiple developmental, psychological, and social challenges after flight. Psychosocial interventions are therefore necessary to support adolescents during the first period after arrival in a receiving country and to avoid negative long-term consequences. Unfortunately, little is known about the types and the effects of such interventions provided during this time. This systematic review aimed to synthesize research about psychosocial interventions for refugee youth during the first year after arrival. Seven studies were identified and showed positive effects on the psychological symptoms of anxiety, post-traumatic stress disorder, and depression, as well as on the personal development of adolescents regarding their life satisfaction, behavioral problems, hope for the future, and their social and cultural integration. Effective elements of the interventions were categorized into trauma-related elements (self-efficacy, safety, and connectedness) and elements associated with forced migration (culture, post-migration environment, and professional network). Nonetheless, the methodological quality of the included studies was heterogenous and the review showed a lack of comprehensive, long-term, and high-quality research in this field. Recommendations for future research include a greater utilization of strong research designs and translated and cross-culturally validated instruments, as well as a focus on elements specifically related to the phase of adolescence.


Introduction
The situation of refugee youth living in receiving countries contains multiple challenges. Developmental tasks of adolescence, experiences of trauma and forced migration and the distinct social requirements of the integration process contribute to the complex vulnerabilities of this group (Kleefeldt et al. 2017;Marshall et al. 2016). Consequently, adolescent refugees are confronted with an increased risk of suffering from mental health issues, social difficulties, and long-term developmental problems (Berthold 2014;El Baba and Colucci 2018;Keilson et al. 1992;Vossoughi et al. 2018). To counteract these negative long-term consequences, the provision of psychosocial interventions, specifically during the initial period after adolescents' arrival in a host country, is needed (Hebebrand et al. 2016;Jakobsen et al. 2014;Leuzinger-Bohleber and Hettich 2018). Additionally, according to the Convention on the Rights of the Child, access to adequate health care, including psychosocial support, is a general right of every child (UNGA 1989). However, it remains unclear as to what kind of intervention studies about the first year after arrival exist, as no previous review was carried out to address this research gap. Therefore, the present review synthesized research about the timely provision of psychosocial interventions for the high-risk group of adolescent refugees living in a complex situation of developmental, psychological, and social challenges after flight.
Adolescence is, in its nature, a significant developmental phase comprising physical and psychological changes. In the context of forced migration, the developmental transformation of social relationships within the family system, the peer group, and society are complicated due to the destabilization of previous family and peer group structures (Grinberg and Grinberg 2004). Moreover, after forced migration, the adolescent must define his/her new role in a receiving society within an unfamiliar culture and community (Tummala-Narra 2014). Apart from the transformation of relationships with others, inner processes that precede during adolescence are aggravated due to forced migration. Since the identity is destabilized not only by development-related processes, but also by forced migration, the identity development is impeded (Grinberg and Grinberg 2004). Moreover, forced migration during adolescence implies a double mourning process, as the adolescent needs to mourn the passing childhood and the loss of the home country (Volkan 2017). Furthermore, documented risk factors on the flight, such as physical or sexual abuse, exploitation, trafficking, trauma, and separation from family members or peers, have an impact not only on the developmental process but also on mental health capacities (Krueger 2018;Menesch and Keller 2016;Ramel et al. 2015). Adolescent refugees are generally at high risk of suffering from psychological disorders (Bornstein and Montgomery 2011;Vossoughi et al. 2018). This was even found during the first period after their arrival in a receiving country (Groark et al. 2011). The most common diagnoses are post-traumatic stress disorder (PTSD), depression, and anxiety disorders (Witt et al. 2015). A recent systematic review on young refugees living in European countries reported prevalence rates from 19 to 53% for PTSD, 10% to 33% for depression, and 9% to 32% for anxiety disorders (Kien et al. 2018). In addition, adolescent refugees are confronted not only with mental health issues, but also with various social difficulties related to the integration process and particularly the asylum procedure. The long-lasting uncertainty about the asylum status, precarious living conditions, and a lack of knowledge about the receiving society, as well as social, cultural, and linguistic barriers, lead to an insecurity about future perspectives (Lewek and Naber 2017;Gravelman 2018;Wieland 2018).
Against this background, the importance of the provision and scientific evaluation of early psychosocial interventions for refugee youth emerges. Those interventions need to be based on the best interest of the child (UNGA 1989) and combine trauma-focused and psychosocial approaches to address the complex needs of adolescent refugees (Miller and Rasmussen 2010). In this context, a previous review identified social support, safety, culture, and education as important psychosocial needs of refugee children and youth (Nakeyar et al. 2018). In addition, other reviews exist on the effectiveness of interventions with refugee youth during later integration phases (Brown et al. 2017;Tyrer and Fazel 2014;Anders and Christiansen 2016). However, no previous review has focused on synthesizing existing psychosocial intervention research with refugee youth within the first year after their flight.

Current Study
After arriving in a receiving country, adolescent refugees are in the midst of a complex process. Many changes due to the developmental phase of adolescence, experienced trauma before or during flight, and the confrontation with social difficulties during the early integration process contribute to a multilayered situation (Jakobsen et al. 2014;Leuzinger-Bohleber and Hettich 2018;Marshall et al. 2016). Thus, the initial time after arrival is crucial for the provision of psychosocial interventions in order to appropriately address refugee youth's needs. In addition, psychosocial interventions serve to counteract mental health problems, as well as social disintegration, and promote positive long-term development. However, it remains unclear in what way the complex needs of refugee youth are reflected in psychosocial interventions and how effective they are. Therefore, this systematic review examined the following questions: (a) What types of psychosocial interventions for refugee youth are implemented during the first year after their arrival in a receiving country? (b) What effects do the interventions show? (c) Which elements of the interventions proved to be effective to treat adolescent refugees in this context?

Method
This systematic review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines (Moher et al. 2015). The searches were carried out in November 2018 using various electronic databases (Web of Science, PsycINFO, PSYNDEX, and PubMed/Medline). Additionally, two German (BAMF, Medico International) and four international (UNHCR, IOM, UNICEF, WHO, Human Rights Watch) websites of governmental and non-governmental organizations, as well as a database of a migration research network (IMISCOE), were searched manually. The searches were performed using the following search strategy: "(refugee* OR asylum* OR displac* OR exil*) AND (youth* OR young* OR adolescen* OR teen* OR minor* OR underage*) AND (psycho* OR social* OR mental*)". During the development of the search strategy, it was decided not to narrow the search to a specific intervention, 1 3 comparison, or outcome, but to follow a rather broad approach to keep the attention on the time criteria.
Quantitative, qualitative, and clinical case studies published since 1990, when the Convention on the Rights of the Child came into force, were included. There was no limitation on publication language or country. Further inclusion criteria were (a) a sample of adolescents aged between 14 and 18 who are (b) asylum seekers or refugees; (c) studies conducted within 12 months after the participants arrived in the host country; and (d) interventions with a focus on psychosocial support or mental health. Studies being excluded were (a) studies examining internally displaced youth or adolescents without own flight experience; (b) studies about health care access and utilization; (c) studies with a focus on specific topics other than psychosocial support or mental health (e.g., education, suicide); (d) studies with a focus on specific target groups (e.g., psychiatric patients, pregnant girls); and (e) inpatient and drug treatments.
The searches generated 7327 references, with an additional 129 reports identified on the websites of the organizations. After the removal of duplicates, 5901 articles remained. 5527 references were excluded after screening of titles and abstracts, mainly because the studies examined prevalence rates and access to health care or ineligible medical diagnosis, treatments, and samples. Two authors of this review evaluated the remaining 374 articles in full-text independently. In the course of the analysis, 12 authors were contacted concerning the participants' length of stay in the host country, two authors concerning the residence status, and two authors concerning both. Ten authors replied and offered detailed information about their samples. After full-text analysis, seven papers remained. The agreement rate of the two reviewers was excellent (κ = 0.90). Disagreements were resolved through discussion, and through the consultation with the third author. The evaluation process is presented in Fig. 1.
Subsequently, the authors extracted data independently from selected studies, using a pilot-tested, standardized data sheet. Two authors assessed study quality using three different assessment checklists: the Downs and Black Quality Index (Downs and Black 1998) (Moola et al. 2017) for clinical case studies. The interrater reliability of the two authors evaluating quality was excellent (κ = 0.95). Disagreements were resolved through discussion.

Characteristics of Included Studies
Seven studies about psychosocial interventions for adolescent refugees within twelve months after they arrived in a receiving country were included for syntheses. Four of those studies evaluated group interventions (Table 1) and three individual approaches (Table 2). Three group intervention studies used quantitative research methods, two studies conducted qualitative analyses, and two studies reported clinical cases. The group interventions were implemented in Australian schools and in a Norwegian reception center. The studies  using individual therapeutic approaches were conducted in the USA and recruited participants via community services or social workers. The total number of participants was N = 220. Sample sizes ranged from 1 to 143. On average, the participants were 15.9 years old and lived in the receiving country for 6.2 months. Four studies examined only male, one study only female participants, and two studies assessed mixed samples. Participants originated from former Yugoslavia, the Middle East, Africa, Southeast Asia, and Central America. All studies were conducted with the help of interpreters. Apart from one exception, different assessment instruments were used. The methodological quality of the included studies ranged from 25.9 to 100% (see Tables 3, 4 and 5). Due to the limited number of publications that met the requirements of this review, no study was excluded based on quality scores. Limitations mentioned by the authors of the included studies were: small sample sizes (Barrett et al. 2000;Bemak and Timm 1994

Psychosocial Interventions
The implemented psychosocial interventions varied regarding their methodological approaches and practical realization. A music education program (Crawford 2017), a standardized anxiety prevention program named FRIENDS (Barrett et al. 2000), the Expressive Arts in Transition program called EXIT (DeMott et al. 2017), and the Home of Expressive Arts and Learning intervention named HEAL (Quinlan et al. 2016) were implemented as group interventions. These interventions focused on the social and personal development of adolescents, anxiety prevention, improvement of trauma and emotional symptoms, as well as hope and life satisfaction. They consisted of 10 sessions respectively, with one intervention offering the opportunity to additionally attend individual sessions if needed (Quinlan et al. 2016). Testimonial Psychotherapy (Lustig et al. 2004), a psychodynamic psychotherapy (Bemak and Timm 1994), and a relational psychodynamic treatment with a traumafocused intervention (Katsounari 2014) were implemented as individual interventions. Those interventions focused on the improvement of trauma symptoms and the evaluation of psychotherapeutic approaches. They lasted between 5 weeks and two and a half years. The individual interventions used exclusively verbal techniques, whereby the Testimonial Psychotherapy was not conducted with the help of interpreters.

Effects of Interventions
All studies reported positive effects of the implemented interventions. The music education program was found to support the personal and social development of refugee adolescents, as well as their cultural and language learning (Crawford 2017). The FRIENDS intervention revealed a significant increase for the control group on internalizing symptoms on the one hand, and a significant decrease in anxiety and depression symptoms for the treatment group on the other hand. After treatment, the participants interpreted ambiguous situations significantly more often as nonthreatening, compared to pre-treatment measurement (Barrett et al. 2000). The EXIT intervention revealed that this art and expression program is suitable for early support and it showed modest long-term positive effects during a 25-month follow-up for the treatment group in mental health complaints. Moreover, life satisfaction and expectations increased more evidently over time (DeMott et al. 2017).
The HEAL intervention demonstrated a significant reduction in emotional symptoms for participants of the treatment group. Furthermore, the results suggested positive effects on behavioral difficulties, hyperactivity, and peer problems (Quinlan et al. 2016). The Testimonial Psychotherapy was found to be feasible, accessible, and safe for male unaccompanied refugee adolescents from Sudan. All participants reported high satisfaction with the therapy (Lustig et al. 2004). The psychodynamic psychotherapies were found to be feasible and an adequate way to improve trauma symptoms in adolescent refugees (Bemak and Timm 1994;Katsounari 2014).

Effective Elements of Interventions
As effective elements, the authors of the included studies described six major themes that contributed to the success of the implemented interventions: self-efficacy, safety, connectedness, culture, post-migration environment, and professional network.

Self-Efficacy
All included studies highlighted the role of self-efficacy and the importance of empowering adolescent refugees, which was reported in various forms. The participants of the music education program experienced the creation of a visible and shared outcome as personal achievement. This evoked confidence and self-assurance and increased personal wellbeing by self-expression in music (Crawford 2017). During the Testimonial Therapy, the adolescents were able to make meaning out of their traumatic experiences, to activate personal resources, to counteract feelings of powerlessness, and to perceive their written testimony as an accomplishment they could share with others. In this context, the authors highlighted that adolescents were in control of the creation, as well as the dissemination, of their testimony and thereby experienced a sense of agency (Lustig et al. 2004). The interventions FRIENDS, EXIT, and HEAL focused on the supporting and teaching of coping strategies for negative feelings and symptoms in order to build a sense of self-agency. During the FRIENDS program, 85% of the participants reported an improvement in dealing with stress and anxiety situations (Barrett et al. 2000). The EXIT intervention focused on the cooperation between participants by implementing various group rituals in each session. Moreover, coping strategies to deal with stress symptoms, and thus enhanced self-confidence, were taught (DeMott et al. 2017). The HEAL program was perceived as helpful in learning how to breath and how to manage difficult life situations, as well as how to create good memories of past experiences (Quinlan et al. 2016). With the improvement of feeling and anger management during the individual psychotherapies, the case studies focused on giving the patient back a sense of control and agency before supporting the process of remembrance and mourning in the second stage of the therapy (Bemak and Timm 1994;Katsounari 2014).

Connectedness
Three intervention studies emphasized the establishment of social networks during the interventions. Music education was found to help refugee youth cooperate, establish social networks, and make friends (Crawford 2017). During the FRIENDS intervention, the participants wished for even more emphasis on family support and relationships during the intervention (Barrett et al. 2000). The EXIT program focused on the need for social ties and social activities to build social networks. The authors proposed that both life satisfaction and hope may have increased as result of the connection to social networks (DeMott et al. 2017). Participants perceived the HEAL program as helpful in terms of creating friendships and being empathetic with other people (Quinlan et al. 2016).
One clinical case study promoted the connection with social networks outside the treatment room (Katsounari 2014).

Safety
Creating a safe space and offering relationships of trust were described as important elements in four of the included studies. The perception of the music teacher as a person of trust PTSD post-traumatic stress disorder, DSM-IV-TR diagnostic and statistical manual of mental disorders-fourth edition-text revision and the music class as a safe space were named as important requirements for the positives effect of the music education program. Thus, the teachers highlighted that adolescents felt safe to engage in the music class and were able to explore their potential (Crawford 2017). By implementing continuity and reliable structures, the FRIENDS intervention promoted the group as a safe space where the adolescents can experience a sense of belonging (Barrett et al. 2000). The clinical case studies highlighted the need to establish a safe space and a trustful relationship without judgment, which serve as a basic stabilization of the patient within the psychotherapeutic process (Bemak and Timm 1994;Katsounari 2014).

Culture
An important aspect of interventions for refugee youth addressed by five of the included studies was culture. The music program, one of the five studies, focused on the intervention's effects on cultural exchange and cultural learning (Crawford 2017). The authors of the other four studies recommended adaptations of the interventions to the adolescents' native cultures. The FRIENDS program found that participants wished for more large-group discussions, more possibilities to verbalize responses, and for more activities on the normalization of cultural differences (Barrett et al. 2000). The participants of the Testimonial Psychotherapy underlined the need to highlight the altruistic benefit of helping friends and family when writing and sharing the testimony, which was interpreted as cultural specificity. Thus, the authors highlighted the importance of introducing the testimony not as clinical work but as a political statement to make it culturally acceptable for the young participants from Sudan (Lustig et al. 2004). The authors of the clinical case studies reported that the consideration of culture-specific norms and beliefs are among the most important aspects considering psychotherapy with young refugees. They suggested the integration of those cultural beliefs and norms and non-Western interventions if appropriate for the patient (Bemak and Timm 1994;Katsounari 2014). One case study further stressed the need to work with the interpreter as a cultural translator (Bemak and Timm 1994).

Post-migration Environment
Four of the included studies demanded the integration of migration-related issues or highlighted the need for a generally supportive post-migration environment to support the interventions. Participants of the FRIENDS program wished for a focus on adjustment difficulties associated with migration and the inclusion of current life issues. The authors mentioned the necessity to understand and integrate the multilayered context by not only focusing on anxiety, but also on family, acculturation, and self-identity issues (Barrett et al. 2000). The case studies described difficulties within the environment in the receiving country as essential to be addressed during therapy (Bemak and Timm 1994;Katsounari 2014). Katsounari (2014) specifically demanded access to education, vocational training, and leisure and recreational activities for refugee adolescents and highlighted the need to consider the current personal situation and the social background of the adolescent. The Testimonial Psychotherapy accounted for the social and political implications of experienced trauma and the need to inform the post-migration environment about those dimensions (Lustig et al. 2004).

Professional Network
The authors of the clinical case studies stressed the importance of cooperating with a professional network. One study recommended the usage of social workers as junior partners in therapy and of interpreters as cultural translators (Bemak and Timm 1994). The other case study highlighted the importance of a stable working alliance with interpreters.  The poor coordination between various actors, as well as insufficient resources, and the existing tension between asylum policies and child protection services were mentioned as reasons to improve network cooperation. Moreover, the need for supervision to avoid the risk of secondary traumatization was mentioned (Katsounari 2014).

Discussion
Shortly after arrival in a receiving country, adolescent refugees experience a difficult phase, being confronted with developmental, psychological, and social challenges at once. Particularly during this time, the implementation of psychosocial interventions addressing those complex needs is important (Guruge and Butt 2015;Jakobsen et al. 2014;Jensen et al. 2014;Leuzinger-Bohleber and Hettich 2018).
Since no systematic research exists in this field, the purpose of the present review was to identify studies on psychosocial interventions for newly arrived refugee youth. It aimed to analyze the outcomes of the interventions and to determine their effectiveness. Seven studies were included for syntheses. Art and psychotherapeutic group interventions, as well as individual psychotherapeutic approaches, showed positive effects on the personal development and the symptom reduction of participants. The variety of the implemented programs underscored that different psychosocial approaches are feasible and can improve the complex integration process of adolescent refugees. Although the studies used different methods in their implementation, the six elements of self-efficacy, connectedness, safety, culture, post-migration environment, and professional network were consistently described as important. For the discussion, those elements were categorized in trauma-related aspects on the one hand, and in elements associated with the experience of forced migration on the other.

Trauma-Related Elements
The included studies described self-efficacy, connectedness, and safety as important components of interventions with newly arrived refugee youth. Although these aspects were already identified in the context of interventions shortly after mass trauma and during the first stage of trauma therapy (Herman 2015;Hobfoll et al. 2007), only one of the included studies referred to those theoretical approaches (DeMott et al. 2017). Nevertheless, this theoretical background explains the importance of the elements counteracting the consequences of trauma. Traumatic experiences are accompanied by the feeling of total powerlessness and destroy inner mental structures, as well as the trust in others and the self (Fischer and Riedesser 2009). Methods promoting self-efficacy can support refugee youth in regaining trust in themselves and a sense of self-agency (Hettich 2018). Additionally, establishing self-efficacy contributes to adolescent identity work, which is especially important in the context of flight (Grinberg and Grinberg 2004). Another aspect to consider is the element of collective efficacy, although this was not addressed by the reviewed studies (Hobfoll et al. 2007). This might partly be due to the impossibility of involving family and community members also affected by the trauma, as four of the included studies examined unaccompanied adolescent refugees only (Bemak and Timm 1994;DeMott et al. 2017;Katsounari 2014;Lustig et al. 2004). Nevertheless, the reviewed studies also focused on connectedness as a trauma-related element. Especially during adolescence characterized by the transformation of social constellations, the support of existing and even transnational social relationships, as well as the promotion of new social networks after flight, is important (Sleijpen et al. 2016). Even though the included studies did not differentiate between categories of social networks, for the well-being and development of adolescent refugees, social relationships within the own community, with other (host) communities, and relationships with social services and state institutions should be specifically considered (Ager and Strang 2008;Correa-Velez et al. 2010;Sleijpen et al. 2016;Trentacosta et al. 2016;Wells 2011). Another important element in the context of trauma mentioned by the reviewed studies is safety, which includes the establishment of a trustful relationship by offering a safe space. In any trauma intervention, this is the basis for a sustainable working alliance and the beginning of a longlasting process of mourning (Herman 2015). Supporting adolescent refugees in their long-lasting mourning process is particularly relevant, as they must not only mourn their childhood, but also the loss of their home country, as well as the experience of trauma at the same time (Volkan 2017). The interrelation of feeling safe and being able to mourn is closely connected to the regaining of hope. The latter was not mentioned in the included studies but noted as important for trauma interventions in previous research (Hobfoll et al. 2007). However, addressing the need for hope is often not possible due to limited opportunities to offer long-term psychosocial interventions, especially during the uncertain situation of the early integration process (e.g., insecurity of acceptance of asylum application, housing situation, language barriers).

Elements Related to Forced Migration
Within the category of elements related to forced migration, culture, post-migration environment, and professional network were identified. Culture, a concept that is controversially discussed (Auernheimer 2002;Hepp 2009;Yampolsky et al. 2013), was mentioned as an important factor in the interventions. Yet, it remained unclear as to how cultural adaptations would particularly influence outcomes of the psychosocial interventions with newly arrived refugee youth. The studies generally referred to culture without considering the impact of interacting factors such as gender, class, religion, ethnicity, and others as demanded by the concept of intersectionality or diversity (Bastia 2014;Lutz et al. 2016). Psychosocial interventions should therefore not focus on culture as a general construct, but consider the best interest of the child, which includes the socialization of participating adolescents, and their personal background (UNGA 1989). Apart from culture, the post-migration environment is another central intervention element related to the experience of forced migration. A positive post-migration environment offering adequate psychosocial support early after arrival is thereby considered as necessary for a positive long-term development of refugee youth (Hebebrand et al. 2016;Kleefeldt et al. 2017;Vervliet et al. 2014). In this context, adolescents should be offered a potential space for individual development, which is often not provided after forced migration (Günther et al. 2010). In contrast, daily hassles and stressful events such as problems with housing, lack of access to health care and education, or discrimination experienced in a host country negatively influence the mental health of refugee youth (Keles et al. 2016;Montgomery 2011;Edge et al. 2014). As the early post-migration environment is highly complex, holistic approaches and an interdisciplinary cooperation of professionals, which was also identified as key intervention elements, are required (Bemak and Timm 1994;Katsounari 2014). The reviewed studies referred specifically to the cooperation between psychotherapist, social workers, interpreters, lawyers, teachers, and social services. This is in line with the findings of Reed et al. (2016) who stressed the importance of cooperation between traditional patient care, case managers, governmental agencies, and lawyers in the context of treatment of refugees. In addition to professional actors, the role of civil society and religious organizations should not be underestimated, since they can be of great importance for young people in the integration process.

Methodological Difficulties in Refugee Research
The heterogenous methodology of the reviewed articles underlined that the uncertain and unstable situation of adolescent refugees during the initial time after arrival in a receiving country complicates the implementation of appropriate study designs (Pacione et al. 2013). Consequently, the study results could only be compared by qualitative interpretation, which is a common difficulty in this field of research (Anders and Christiansen 2016;Montgomery 2011;Tyrer and Fazel 2014;Brown et al. 2017;Peltonen and Punamaki 2010). Future research should focus on comprehensive study designs and on the examination of larger sample sizes, the application of standardized interventions and equivalent instruments, the implementation of follow-ups, and the usage of mixed methods for a better understanding of the complex situation of refugee youth (Sleijpen et al. 2016;Weine et al. 2014). When examining newly arrived refugee youth, linguistic barriers are a specific methodological challenge. Although this obstacle can be overcome by using creative art techniques, studies using verbal techniques often have stronger study designs and better quantitative results (Tyrer and Fazel 2014). Furthermore, another problem is that most of the assessment tools used in research with refugees are not reliably translated and cross-culturally validated (Hollifield et al. 2002). When using interpreters during psychosocial intervention studies, the provision of sufficient training about the fulfillment of the professional role in psychosocial interventions and during the research process is obligatory. In this regard, further research must increase the transparency in the research process and in publications.

Limitations and Strengths of the Study
This is the first systematic review on psychosocial interventions for refugee youth within one year after their arrival in a receiving country following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols guidelines (Moher et al. 2015). However, several limitations of the present review need to be noted. The literature search was limited to four databases and eight governmental and non-governmental organizations' websites. Although the inclusion of those websites is a strength of the review, more considerations about how to include gray literature and reduce publication bias are necessary to draw a more comprehensive picture of the existing literature. More efforts could have been made to include studies by organizations and research groups from developing countries, as the current review only identified studies conducted in high-income countries. Another limitation was the broad approach including all kinds of psychosocial interventions, as well as different methodological types of research, which complicated the comparison of studies. Nevertheless, given the limited number of papers in this emerging field, the broad inclusion criteria could not be avoided. The different backgrounds of the authors, combining a psychological and social work perspective, need to be mentioned as an additional strength of the study, as it underlines the importance of interdisciplinary research in this field.

Conclusion
Adolescent refugees are confronted with multiple developmental, psychological, and social challenges after arriving in a receiving country. To address these difficulties, the provision of early psychosocial interventions is important, as it contributes to healthy long-term development. Nevertheless, this systematic review identified a gap in intervention research on psychosocial support for refugee youth in receiving countries during the first year after arrival. Only seven studies were included. The reviewed studies consisted of a variety of psychosocial interventions ranging from individual psychotherapies to creative art or psychotherapeutic group interventions. All interventions showed positive effects on the personal development or symptom reduction of adolescents. Even though different interventions were implemented, all authors stressed elements related to trauma (self-efficacy, safety, and connectedness) and forced migration (culture, post-migration environment, and professional network) as being important aspects of the interventions. Apart from those elements, the best interest of the child and especially the specific needs of youth development during forced migration ought to be the guiding principles of psychosocial interventions with refugee youth. Consequently, psychosocial practice, as well as future research with refugee youth, need to consider the complexity of the interrelation between the long-term developmental, psychological, and social needs of adolescent refugees during the integration process. To fulfill those requirements, sustainable structures, financial resources, and interdisciplinary cooperation allowing for long-term psychosocial interventions with refugee youth, even during the uncertain situation of the early integration process, are needed.
Authors' Contributions NH conceived of the study, developed the research question and search strategies, conducted literature searches, screening process, data extraction, and quality assessment, performed interpretation of findings, drafted and revised the manuscript; FAS conducted literature searches, screening process, data extraction, and quality assessment, performed interpretation of findings, drafted and revised the manuscript critically; LYS contributed to the research design and search strategies, conducted literature searches, supported the screening process, drafted and revised the manuscript critically. All authors read and approved the final manuscript.
Funding Open Access funding enabled and organized by Projekt Deal.

Compliance with Ethical Standards
Conflict of interest The authors report no conflict of interests.
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