PROTOCOL: Child and adolescent mental health and psychosocial support interventions: An evidence and gap map of low‐ and middle‐income countries

Abstract This is the protocol for a Campbell review. The objective of this evidence and gap map is to provide an overview of the existing evidence on the effectiveness of interventions aimed at promoting mental health and reducing or preventing mental health conditions among children and adolescents in low‐ and middle‐income countries.

1 | BACKGROUND 1.1 | The problem, condition or issue All children have the right to opportunities to survive, grow and develop, within the context of physical, emotional and social wellbeing, to achieve their full potential (UN, 2013). Mental health has been defined as 'a state of well-being in which the individual realises his or her own abilities, can cope with the normal stresses of life, can work productively and fruitfully, and is able to make a contribution to his or her community' (WHO, 2004, p. 11). While this definition moves away from the conceptualisation of mental health as solely the absence of illness, most research and prevalence studies on children and adolescents focus on the mental health conditions that affect mood, thinking and behaviour.
Indeed, it is estimated that globally mental health disorders affect about one in seven children and adolescents aged 10-19 (UNICEF, 2021). The magnitude and nature of child and adolescent mental health conditions can be illustrated through several key figures. First, and despite significant variation, the worldwide pooled prevalence of mental health conditions among children ages 10-19 is estimated at 27.5% for anxiety disorder and 12.7% for depression, which are often comorbid (UNICEF, 2021). Second, depression is among the leading causes of disability among young people while suicide is a leading cause of death among adolescents worldwide, the third among 15-19-year-old adolescent girls (UNICEF, 2021). Lastly, most mental health conditions originate early in life, with 50% arising before the age of 14% and 75% by the mid-20s (Kessler et al., 2010;Solmi et al., 2021). Yet, despite its prevalence, the evidence on effective interventions addressing the mental health and psychosocial well-being of children and adolescents has not been consistently gathered and mapped (Kieling et al., 2011).
Across the phases of life, experiences and environment present potential risks and opportunities for children and adolescents.
Mounting evidence has shown that the first 1,000 days represent a unique opportunity for unparalleled cognitive growth and early stimulation which are central to healthy mental and emotional lives (Erskine et al., 2017;Klasen & Crombag, 2013;Patel et al., 2018).
During the early years of a child's life, parents and caregivers are instrumental in shaping child development and behaviour through proper child nutrition, education and a nurturing and safe home environment. Middle childhood (5-9 years) are school-going years that provide the context for early peer support and nurturing care through positive interactions as well as providing opportunities for building important life skills (Kieling et al., 2011).
Adolescence is a second window of opportunity, where critical period in brain development is taking place and where adolescents adopt and maintaining social and emotional habits and are engaged in identity formation. This period is characterised by a heightened salience of relationships with peers, which become key factors in shaping and directing young people's psychological development (Mitic et al., 2021). The onset of puberty at this stage brings unique mental health challenges compounded by physiological and emotional transitions, as well as sexual and risk-taking behaviours. Late adolescence (15-19 years) is shaped by community and social and cultural expectations of acceptable behaviour, gender norms and roles, and the upper end of adolescence comes with pressure to secure employment and gain social and economic independence.
At the same time, evidence highlights that adolescence is a time when young people harness skills and traits that can foster resilience, or the learned capacity to deal more effectively with ongoing adversity (Lansford & Banati, 2018). Effective positive coping strategies and behaviours adopted and learned during these years can reap benefits into adulthood. In addition, adolescence offers an opportunity to overcome early adversities. Although most children can adequately recover and adapt using their own resources, childhood and adolescence are also vulnerable periods during which adverse experiences can negatively impact cognitive, emotional, and behavioural development. Exposure to adverse experiences during these and earlier years means that without care and support some children and adolescents may carry the mental and emotional costs for years to come (Haahr-Pedersen et al., 2020).
Despite the high burden and early onset, most mental health conditions remain unrecognised and untreated. A global systematic review of survey data in 2004 estimated that 70% of people aged 15 and older who were living with mental health conditions lacked access to adequate care (Kohn et al., 2004) and that this gap is higher in lowand middle-income countries (LMICs), where most children and young people live (90%; Kieling et al., 2011). This estimate may have changed in the last decade, and it is important to assess the evidence and treatment gaps in LMICs in more recent years. Additionally, there is growing evidence of effective, affordable and culturally acceptable interventions from high-income settings for preventing and treating mental health conditions that can be implemented in LMICs (Das et al., 2016). School-based programmes can have significant positive effects on children and adolescents' well-being, including reduced depression and anxiety and improved coping skills (Barry et al., 2013).
Various promotion and prevention approaches have been successfully implemented and rolled-out in health and community settings (Bradshaw et al., 2021;Das et al., 2016;Klasen & Crombag, 2013;Skeen et al., 2019). Parent and family-focused interventions (i.e., psychoeducation, parent and family-skills training, behavioural, psychosocial, and trauma-focused cognitive behavioural therapy) may be beneficial to child and youth mental health and well-being, as well as parenting behaviours and family functioning (Pedersen et al., 2019).
1.2 | Why it is important to develop the evidence and gap map (EGM) Investment in child and adolescent mental health prevention, promotion and care is essential but the evidence from this field is yet to be consistently systematically collected and mapped. An EGM would assist in generating a clearer picture of the available evidence on interventions to improve child and adolescent mental health in low-resource settings, thereby informing future research, policy and practice.
Promoting, protecting and caring for children and young people's mental health plays a key role in achieving most of the 17 sustainable development goals (SDGs). More specifically, Goal 3 calls on Member States to ensure healthy lives and promote well-being for all at all ages.
More specifically, SDG target 3.4 is to reduce premature mortality from non-communicable diseases and to promote mental health and wellbeing. Effective mental health interventions could act as potential development goal accelerators (Sherr et al., 2020)-with provisions that lead to progress across domains of a child's life, and impacting multiple SDGs (Patel et al., 2018). However, mental health care is underprioritised and under-funded, representing just up to 1% of national budgets in LMICs (Patel et al., 2018). In the context of meeting these global goals, identifying what works in the field of mental health and psychosocial support in low-resource settings and mapping potential areas of investment for future research and programming gains urgency.
Early evidence from the COVID-19 crisis indicates exacerbated mental health problems during the pandemic, with children and young people globally at risk of psychosocial distress, including anxiety, depression, and externalising behaviours, due to lockdowns, school clo- Against such a backdrop, UNICEF has renewed its commitment by setting a new goal to secure investment and action to support and protect the mental health of children and young people. At present, 90% of research on child and adolescent mental health has been conducted in high-income countries and evidence from low-resource settings is sparse (Kieling et al., 2011). An EGM would serve to identify where the evidence is abundant, but also where limited research and absolute gaps exist and increase the visibility of the available evidence . This resource will allow us to identify underresearched areas, countries and population sub-groups and inform the decisions of international donors, policymakers, practitioners and researchers as well as UNICEF's research priorities and programmatic actions. A visual representation of the evidence, in the form of a matrix of interventions, will allow practitioners, researchers, donors and policymakers to identify and focus on the areas of research that are more likely to inform their work.

| Existing EGMs and/or relevant systematic reviews
A brief desk-based scoping was conducted to inform the objectives of this EGM, which identified several EGMs covering adjacent topics and themes, and systematic reviews that explore a subset of the inter- In addition to available and upcoming EGMs, a number of systematic reviews have investigated specific subsets of mental health interventions, outcomes and populations, and will be considered according to our inclusion and exclusion criteria. Barry et al. (2013) reviewed the evidence on the effectiveness of mental health pro-  (Laurenzi et al., 2020). A metaanalysis identified effective programme components of interventions to promote mental health and prevent mental disorders and risk behaviours during adolescence. In a review of systematic reviews, Das et al. (2016) synthesised the evidence on mental health intervention for adolescents, including but not limited to virtual, individual, group, family and school-based interventions. Another review investigated programmes aimed at promoting mental health and preventing mental disorders and risk behaviours during adolescence (Skeen et al., 2019). Klasen and Crombag (2013) identified a series of affordable and feasible interventions for children and adolescents in low-resource settings. van Ginneken et al. (2013) and van Ginneken et al. (2021), respectively, analysed the effectiveness of nonspecialist and primarly-level worker mental health and psychosocial support interventions on child and adolescent mental health.
We also identified and reviewed relevant intervention guidelines and their supporting evidence to define our scope and identify key the social determinants of health approach (Marmot & Wilkinson, 2005) which emphasises the role of circumstances in which people are born and grow up, as well as the systems in place to deal with illness; and (c) the life course epidemiology approach (Kuh et al., 2003) which highlights the factors and experiences over the life course and across generations that impact health outcomes at different ages and life stages.
The EGM utilises this framework by organising interventions according to delivery platforms that correspond to the levels in a child's social ecology. Further, the outcomes will be sensitive to the child's life stage and social determinants of health, thereby including child development outcomes as well. Child and adolescent mental health is complex and changes over time according to individual characteristics, relationships, context and experiences. Therefore, child and adolescent mental health is hereby understood to encompass both negative and positive mental health outcomes including well-being and functioning as well as symptoms of distress or sadness and mental health conditions that may require specialised care.
Building on this, we will be applying the continuum of care model to categorise mental health interventions as prevention, promotion or treatment, as depicted in Figure 1  Treatment interventions are for populations living with a mental health condition. The framework also includes recovery interventions; however, these interventions will be excluded from the EGM (Figure 2).

| OBJECTIVES
The objective of this EGM is to provide an overview of the existing evidence on the effectiveness of interventions aimed at promoting mental health and reducing or preventing mental health conditions among children and adolescents in LMICs.
F I G U R E 1 Child and adolescent mental health and psychosocial well-being: A conceptual framework for research and evidence generation and use (Idele et al., forthcoming) F I G U R E 2 Mental health intervention spectrum (Institute of Medicine, 1994) Consistent with this, the EGM will: 1. Identify, describe and visually represent the existing evidence from systematic reviews and primary studies on the effectiveness of mental health interventions for children and adolescents.
2. Identify existing gaps in evidence to better inform practice and future primary research.
3. Identify clusters of primary studies that offer opportunities for evidence synthesis.

| EGM: Definitions
In contrast to systematic reviews, EGMs do not aim to synthesise the outcomes or key messages from available evidence, but instead aim to map the availability of evidence, coverage and gaps across the various dimensions of the EGM framework and make the evidence discoverable, accessible and usable. EGMs provide an overview of the existing evidence on a topic, theme or sector to signpost where evidence exists and/or where it is lacking (Bakrania, 2020).

| Types of population
Children and adolescents are defined as any person from 0 to 19 years of age and classified according to UNICEF's age criteria stated as follows: early childhood (0-4 years), middle childhood (5-9 years), early adolescence (10-14 years) and late adolescence (15-19 years).
Primary studies where less than 50% of the sample fall within the 0-19 age range or that do not provide sufficient information of age composition will be excluded.
Population subgroups of interest includes children in alternative care, children with disabilities, LGBTQIA + children, ethnic or racial minorities, child workers, married children, street children, children with chronic health conditions, pregnant adolescents and adolescent parents and forcibly displaced children. Studies that disaggregate findings by these population subgroups will be coded as such. We will also note whether studies or reviews focus on girls/females, boys/ males and/or other.
LMICs are defined according to the World Bank's regional classification by country gross national income as: low-income, lower middle-income, upper middle-income economies (The World Bank, 2021).

| Types of intervention
Mental health and psychosocial support is defined as 'any type of local or outside support that aims to protect or promote psychosocial well-being and/or prevent or treat mental disorders' (Inter-Agency Standing Committee, 2007, p. 1). As such, the primary aim of mental • Promotion: activities and programs focusing on strengthening positive aspects of mental health and child well-being.
• Prevention: activities and programs that aim to stop mental health conditions from developing, by acting on the social determinants of mental health that may be known risk factors for certain mental disorders.
• Treatment: activities to reduce symptoms and improve functioning in people with identified mental disorders. We will exclude pharmacological treatment.
The distinction between interventions that enhance mental health and those that lower the risk of or ameliorate mental health conditions is not always clear (Supporting Information Appendix 1; Tol et al., 2015). Therefore, although we include examples of interventions for each intervention type, it should be noted that there may be overlaps, for example, a cognitive behaviour therapy intervention can be classified, depending on its objectives and modules, as promotion if it is focused on building life skills or treatment if it teaches children how to cope with and overcome anxiety). Recovery interventions focused on compliance with long-term treatment with the goal of reducing relapse and recurrence as well as after care and rehabilitation will be excluded from the EGM. We will exclude studies investigating the effectiveness of neurofeedback.  Committee, 2021). In additon, we have also included 'other' categories for relevant outcomes that may emerge from the included studies and relate directly to the outcomes described above (e.g., sadness or hopelessness as outcomes related to depression, or self-efficacy and prosocial behaviours as outcomes related to mental well-being). To capture key early childhood indicators, we will also be looking at child development outcomes such as social emotional learning and cognitive development. These are critical processes through which children acquire and apply knowledge and skills to cope with challenges, manage interpersonal relationships, manage emotions, solve problems, and make informed decisions. These indicators are also linked to later life mental health outcomes (Black et al., 2017;Patel et al., 2018).

| Types of study designs
The study designs which will be included in the EGM are: systematic reviews and effectiveness studies in the form of randomised control trials and quasi-experimental studies. Mixed-methods studies with a focus on intervention effectiveness will also be included. These types of study designs match the focus on intervention effectiveness. We will not include qualitative studies in the EGM or quantitative and mixed-methods studies with focus on topics beyond intervention effectiveness such as training and capacity building of practitioners and providers, detection and diagnosis of mental health conditions, single case reports of treatments, other EGMs, systematic reviews of reviews, natural experiments and research on mental health policy or legislations.

| Types of settings
Interventions delivered in hospital settings such as in-patient psychiatric care are considered beyond the scope of the map's delivery platforms and will not be included in the EGM. Peer-reviewed reports and academic papers will be included. Protocols of systematic reviews and primary studies will be also included and removed if the review or primary study is identified. Pilots of randomised controlled trials will be excluded. Co-registered reports will be treated as duplicate reviews with data extracted from the most detailed version. Similarly, if multiple versions of the same systematic review are identified, the latest and most comprehensive version will be considered for inclusion. Commentaries, conceptual or theoretical papers, editorials, conference proceedings and clinical cases will not be included.

| Languages
Searches will be conducted in English, but studies and reviews written in any language will be considered for inclusion.

| Search structure
The search will have four blocks: population, interventions, outcomes, and geography. Where available, we will use the existing search filters (such as EPOC filter for Low-and Middle-Income Countries).

| Search process
The information specialist (FS) will design and test the draft search strategy for MEDLINE via Ovid SP (Supporting Information Appendix 2).
The strategy will be shared with review team and well as the Advisory Board for commenting and revisions. The final search strategy and search resources will be discussed and agreed within the review team before translation into the syntax of other databases and running the final search. The search will be designed following the Chapter 4 of Cochrane Handbook, peer-reviewed using PRESS guideline, and reported based on PRISMA-Search.

| Databases
A wide range of bibliographic databases, sources of grey literature, and websites will be searched to cover all the relevant subject areas, geography, and study designs. The primary list of databases is as follows:

• ProQuest Dissertations & Theses Global
Screening and study selection All titles and abstracts, and then full text, will be double screened, with a third-party arbitrator in the event of disagreement.
Screening will be conducted using EPPI-Reviewer Web (Thomas et al., 2020). The screening tool is given as Supporting Information Appendix 3. Due to time and resource limitations, if the number of retrieved records exceed 10,000 at title and abstract we will employ EPPI-Reviewer's machine learning and priority screening functions to automatically exclude records with a low probability of meeting the inclusion criteria.

Data extraction and management
Data extraction will be conducted using EPPI-Reviewer Web. Due to the expected large volume of reviews meeting inclusion criteria, a small sample of studies and reviews will be extracted by two reviewers and disagreements will be resolved by consensus.
The remaining coding will be conducted by one reviewer independently, in consultation with other reviewers when necessary.

Critical appraisal
Due to the expected large volume of studies and reviews meeting our inclusion criteria, we will not be appraising the quality of included studies and reviews. Instead, we will collect data on study design and type of systematic review as well as the number of participants included in each primary study or the number of studies within each review. In the final report, we will discuss the implications and sources of bias introduced by each type of design or review.

Methods for mapping
EPPI-Mapper will be used to develop the EGM.

| Analysis and presentation
Presentation Each entry in the map will be a systematic review or a primary study of effectiveness. The final EGM will identify the number of studies covered by the map according to each intervention and outcome dimension. The available evidence will be represented across two dimensions: the rows list interventions and the columns list outcome domains. Each cell will show studies and reviews which contain evidence on that combination of intervention and outcomes or absolute gaps when no evidence exists. The number of included primary studies and reviews will be shown by the size of the bubble and the type of design or review will be indicated by the colour of each bubble. In addition to the dimensions (i.e., interventions and outcomes), Table 3 presents the filters of the EGM.

Planned analysis
The EGM report will provide tabulations and/or graphs of the number of studies, with accompanying narrative description, by: • Intervention category and subcategory • Humanitarian context: Study or review explicitly mentions that the MHPSS intervention (as defined by IASC guidelines) was conducted in a humanitarian or conflict-affected region.
• COVID-19: Study or review explicitly mentions having been conducted in the context of the COVID-19 pandemic or including studies conducted in the context of the COVID-19 pandemic.

Study design
• Systematic review-Narrative synthesis • Systematic review-Meta-analysis or meta-regression • Systematic review-Narrative synthesis and meta-analysis or meta-regression • Primary study-Randomised controlled trial • Primary study-Quasi-experimental study • Primary study-Mixed-methods study • Protocol of systematic review or RCT • Threshold of number of participants or number of studies SHARMA ET AL.
| 9 of 12 program issues, as they relate to adolescents and young people.
She has close to 20 years of international development experience with the UN and other international organisations, providing strategic advice on adolescent development and sensitive issues.

DECLARATIONS OF INTEREST
None known.

PLANS FOR UPDATING THE EGM
Once completed, the EGM will be updated yearly, depending on the need of an update (availability of new reviews and primary studies).
Regular updates are also subject to availability of funding. If funding is available, UNICEF Office of Research-Innocenti takes responsibility for updating the review.

SOURCES OF SUPPORT
Internal sources • UNICEF Office of Research-Innocenti, Italy The funding for this EGM is provided by UNICEF Office of Research-Innocenti.

External sources
• Not Applicable