This paper was guided by the Consolidated Standards of Reporting Trials (CONSORT) (Figure 1) and the Standards for Reporting Implementation Studies (StaRI) Checklists (Additional Files 1 & 2).
Study Design
The RESETTLE-IDPs study employs a cluster-randomized type 2 hybrid effectiveness-implementation trial design (44). This design allows for the simultaneous evaluation of the clinical effectiveness of the LSE intervention on mental health outcomes and the assessment of implementation outcomes to inform potential scale-up and sustainability (45). The design will also allow the comparison of the in-person and the mobile arm.
The study will be conducted in two phases using a community-partnered participatory approach :
- Phase 1) a formative phase to culturally adapt the LSE intervention and engage stakeholders; and
- Phase 2) an intervention phase to evaluate the effectiveness and implementation of the LSE program delivered through in-person peer support groups or Mobile -facilitated peer groups.
Study Setting and Participants
The study will be conducted in IDP host communities in Maiduguri, the capital of Borno State in Northeast Nigeria. Since the emergence of the Boko Haram conflict in 2009, Maiduguri has become the hub of IDPs and hosts the highest proportion of IDPs in the country, 76%. An estimated 49% of these IDPs reside in 237 camp/camp-like settings, and 51% are in host communities (4) . The IDP host communities will be our unit of randomizing. Selection criteria for our two study sites include population size, non-existence of MHPSS, network availability, and the presence of local partners and infrastructure to support the research.
The target population includes IDPs 13 years and older who have been displaced for at least three months. Participants will be recruited through a combination of purposive sampling strategies, with the assistance of camp leaders, community mobilizers, and humanitarian organizations in those sites, given the intervention delivery approach: in-person and mobile arm group. Inclusion criteria are: 1) resident in IDP camp for 6 months; 2) aged 18 years or older; 3) speaks English or Hausa; 4) having access to a mobile phone or being willing to share one (for the Mobile, i.e., WhatsApp, arm); and 5) providing informed consent/assent. It is important to note that while device sharing is allowed for participation in the Mobile arm, it may pose potential risks to participants' privacy and confidentiality. Measures will be taken to mitigate these risks, such as providing guidance on secure device sharing practices and ensuring that shared devices have appropriate security features enabled.
Exclusion criteria include 1) the presence of mental illness, cognitive impairment, or substance abuse that would hinder meaningful participation following the baseline assessment; 2) imminent risk of suicide or violence requiring immediate referral; and 3) unwillingness to participate in the study or complete study assessments.
Sample Size and Power Analysis
The target sample size of 500 participants (250 per arm) was calculated based on the primary outcome of change in PTSD symptoms, as measured by the PCL-5. The sample size was determined to detect a minimum effect size (Cohen's d) of 0.4, which represents a clinically meaningful difference in PTSD symptoms between the two intervention arms. This effect size is consistent with previous studies of psychosocial interventions for conflict-affected populations (46). The power calculation assumed a two-sided significance level of 0.05, a power of 80%, and an intra cluster correlation coefficient (ICC) of 0.05 to account for the clustering of participants within IDP camps or communities. The ICC was estimated based on previous cluster-randomized trials of mental health interventions in humanitarian settings (47). To account for potential attrition, the sample size was inflated by 15%, based on an anticipated dropout rate of 10-15% over the 12-week intervention period. This attrition rate is consistent with previous longitudinal studies of IDPs and takes into consideration the potential challenges of retention in the context of ongoing displacement and insecurity(48).
Based on these parameters, a total of 20 clusters (10 per arm) with an average of 25 participants per cluster (500 participants in total) will provide sufficient power to detect a clinically meaningful difference in PTSD symptoms between the in-person and mobile-delivered LSE interventions, while accounting for clustering and attrition.
The Adapted Evidence-Based Intervention
The LSE intervention will consist of a culturally adapted curriculum covering core life skills topics such as stress management, communication, problem-solving, goal setting, health and hygiene, safety and protection, and social support. The curriculum will be developed through a participatory process involving IDP men and women, community leaders, mental health experts, and humanitarian actors, drawing on existing evidence-based resources, particularly the UNICEF Comprehensive life skills framework (49).
Agencies of the United Nations list the ten core life skill strategies and techniques as: problem solving, critical thinking, effective communication skills, decision-making, creative thinking, interpersonal relationship skills, self-awareness building skills, empathy, and coping with stress and emotions (50) (Figure 2). These skills will be categorized into an initial group of skills that contribute to the four outcome areas of life-long learning, employability and entrepreneurship, personal empowerment, and active citizenship (51). These transferable skills are building also helps prevent aggressive and conflict inducing behaviour later in life and is essential to any post-crisis reconciliation, social cohesion and longstanding peace (51).
In the in-person arm, participants will attend weekly 120-minute peer support group sessions facilitated by trained IDP men and women and supervised by local mental health workers. The groups will be gender- and age-segregated (13-15, 16-19, and 18+ years) to create safe spaces for open discussion and skills practice. Sessions will employ interactive and experiential learning techniques such as role-plays, storytelling, games, and art-based activities to enhance engagement and retention.
In the mobile arm (i.e WhatsApp), participants will join gender- and age-specific mobile groups moderated by trained facilitators. The groups will receive weekly LSE content and exercises through a combination of messages, voice notes, images, and live audio sessions. Participants will be encouraged to share reflections, ask questions, and provide peer support through the WhatsApp chat. Facilitators will stimulate discussion, offer feedback, and monitor participant safety and engagement.
Both arms will receive the LSE intervention for a duration of 12 weeks, with an average of 10-12 participants per peer support group. Fidelity to the intervention will be assessed through structured observations, attendance records, and facilitator logs (52). Participants will receive the equivalent of $20 US and be provided with snacks during the intervention. Participants will also have access to referral information for additional mental health and social services as needed.
Theory of Change
The RESETTLE-IDPs study is guided by a theory of change that posits a pathway from the LSE intervention to improved mental health and well-being outcomes among IDPs (Figure 3). The LSE intervention is hypothesized to lead to a series of proximal outcomes, including:
- Increased knowledge and awareness of coping strategies
- Enhanced problem-solving and decision-making skills
- Improved communication and interpersonal skills
- Increased emotion regulation and stress management abilities
- Greater sense of self-efficacy and agency
- Strengthened social support and connectedness
These proximal outcomes are expected to mediate the effect of the LSE intervention on the primary outcome of reduced PTSD symptoms, as well as the secondary outcomes of reduced depression and anxiety symptoms and improved well-being. The theory of change also recognizes the potential moderating effects of individual, social, and contextual factors on intervention effectiveness and implementation.
By articulating the hypothesized causal pathways and mechanisms of change, the theory of change provides a conceptual framework for designing the intervention, selecting measures, and analyzing results. It also helps to identify key constructs and processes to be assessed in the process evaluation to elucidate how and why the intervention works in this context. The theory of change will be refined based on study findings and stakeholder input to inform future implementations and adaptations of the LSE intervention for IDPs.
Outcomes and Measures
The study outcomes will be guided by the Reach-Effectiveness-Adoption-Implementation-Maintenance (RE-AIM) framework (53). Reach will assess the number, proportion, and representativeness of IDP men and women participating in the LSE intervention. Effectiveness will evaluate the intervention's impact on primary and secondary clinical health outcomes. Adoption will determine the uptake of the LSE intervention among IDP camps and humanitarian organizations. Implementation will examine the fidelity, consistency, and cost of delivering the intervention. Finally, maintenance will evaluate the long-term sustainability using camp reports and LSE intervention within organizational and state programs (Table 1). To maximize the program’s impact, we will assess both its clinical effectiveness and implementation processes. By comprehensively assessing these dimensions, we aim to optimize the intervention's impact and inform future implementation efforts
Table 1 Outcome measures defined by the RE-AIM framework
RE-AIM Outcome
|
Operational Definition
|
Measures
|
Reach
|
The absolute number, proportion, and representativeness of IDP men and women who participate in the LSE intervention.
|
- Number and percentage of eligible participants who enroll in the study
- Demographic and clinical characteristics of participants compared to the target population
|
Effectiveness
|
The impact of the LSE intervention on primary and secondary mental health outcomes among IDP youth and women.
|
- PTSD symptoms (PCL-5)
- Depression symptoms (PHQ-9)
- Anxiety symptoms (GAD-7)
- Well-being (WHO-5)
- Life skills acquisition (locally developed measure)
|
Adoption
|
The absolute number, proportion, and representativeness of IDP camps and humanitarian organizations that agree to deliver the LSE intervention.
|
- Number and percentage of IDP camps that participate in the study
- Number and types of humanitarian organizations that support the intervention
|
Implementation
|
The fidelity, consistency, and cost of delivering the LSE intervention as intended in real-world IDP settings.
|
- Adherence to the LSE curriculum and delivery protocol (facilitator logs, observations)
- Dosage of intervention received by participants (attendance records)
- Quality of intervention delivery (participant ratings, facilitator competence)
- Adaptations made to the intervention during implementation (facilitator logs, interviews)
|
Maintenance
|
The extent to which the LSE intervention becomes institutionalized or part of routine humanitarian programming for IDPs over time.
|
- Continuation of the LSE intervention beyond the study period (camp reports, observations)
- Integration of the LSE intervention into existing humanitarian services (organizational policies, budgets)
- Sustained effects of the intervention on mental health outcomes at 6 and 12-month follow-up (PCL-5, PHQ-9, GAD-7, WHO-5)
- Perceptions of the intervention's sustainability and scalability (stakeholder interviews)
|
Clinical outcomes will focus on primarily the intervention effectiveness in in changing PTSD symptoms from baseline to post-intervention (12 weeks), as measured by the Post-Traumatic Stress Disorder Checklist for DSM-5 (PCL-5) (54). The PCL-5 is a 20-item self-report measure that assesses the presence and severity of PTSD symptoms on a 5-point Likert scale, with higher scores indicating greater symptom severity. The measure has been validated in several cultural contexts and shows good psychometric properties and will be validated to the local Hausa Language (55). Secondary outcomes include changes in depression symptoms (Patient Health Questionnaire-9), anxiety symptoms (Generalized Anxiety Disorder-7), well-being (WHO-5), and life skills acquisition (locally developed measure) (56–58).
Implementation outcomes will assess the acceptability, appropriateness, fidelity, and feasibility of the intervention. To gain a deeper understanding of these factors, a qualitative process evaluation will be conducted throughout the study. This evaluation will explore factors influencing program delivery, participant experiences, and program outcomes, including barriers and facilitators to implementation. Data will be collected through in-depth interviews with program facilitators, key stakeholders, and participants, as well as focus group discussions and observations. By examining the intervention's processes, we aim to inform post-project sustainability and scaling plans. Outcomes will be assessed at baseline, three months, and at the follow up periods of six months and 12-month follow-up by trained research assistants.
Data Collection and Management
To gather in-depth data on the LSE intervention, we will employ a mixed-methods Quantitative data will be collected using a combination of interviewer-administered questionnaires and self-interviewing. Questionnaires will be translated and back-translated into Hausa and pilot-tested for comprehension and cultural appropriateness. Data will be entered into a secure, password-protected database using unique participant identification numbers to maintain confidentiality.
Qualitative data from participants, program facilitators and stakeholders will be collected through facilitator logs, in-depth interviews, focus group discussions, and participant observations. Interviews and discussions will be audio-recorded and stored in secured system, transcribed verbatim, and translated into English by external vendors, for analysis. All transcribed, anonymized and translated interviews will be reviewed by the study team for accuracy before analysis. Field notes and memos will be used to capture contextual details and researcher reflections. Data quality will be ensured through regular monitoring, double data entry, and range and consistency checks.
Data Analysis
Implementation outcomes will be assessed using the Acceptability of Intervention Measure (AIM), Intervention Appropriateness Measure (IAM), Facilitator Fidelity logs, observation checklist of program implementation and observation of staff training on the life skills curriculum, and Feasibility of Intervention Measure (FIM)(59). Cost-effectiveness will be calculated by estimating the total program costs and comparing them to the achieved health outcomes.
Qualitative data analysis will employ a reflexive thematic analysis approach using both inductive and deductive coding strategies to identify key themes related to implementation, acceptability, fidelity, and feasibility. Transcripts will be coded iteratively to identify emerging themes and patterns, with constant comparison within and across cases. Memos and matrices will be used to facilitate synthesis and interpretation. Triangulation of qualitative and quantitative findings will be performed to enhance validity and identify convergent and divergent results (60,61).
Quantitative data analysis will follow an intention-to-treat approach, using mixed-effects linear regression models to assess intervention effects on primary and secondary outcomes. Models will include fixed effects for time, group assignment, and their interaction, and random effects for clusters and participants. Baseline characteristics will be included as covariates to adjust for potential confounding. missing data will be handled using list wise deletion (complete case analysis) or multiple imputation (MI)methods.
Effect sizes will be expressed using Cohen’s (standardized mean differences) with 95% confidence intervals. To account for potential biases from unmeasured confounders, propensity score matching will be employed to adjust the effect size estimates.
intervals. Subgroup analyses will explore differential effects by gender, age, displacement duration, and baseline symptom severity. Sensitivity analyses will be conducted to assess the robustness of the findings to different assumptions and methods.