Assumptions and preconceptions.

We recognized the urgent need for mental health support among individuals with opioid use disorder in Ukraine. We also acknowledged several assumptions that could have influenced our approach: a) the expectation that SH+ and PM+ would be well-received due to their previous success in other humanitarian settings; b) the belief that stigma surrounding opioid use and mental health might pose a barrier to participation; c) the assumption that group-based interventions (SH+) could be more difficult to implement than individual interventions (PM+) due the personal nature of trauma and distress. To mitigate potential biases, we designed the study to allow participants to openly express both positive and negative experiences with the interventions. This ensured that acceptability was assessed from their perspectives rather than our expectations.

Positionality and power dynamics.

Conducting research in conflict-affected environments requires careful consideration of power dynamics. As researchers associated with European and Ukrainian institutions, our institutional authority and perceived expertise affected our interaction with participants in OAT centers. To reduce power imbalances: a) we conducted the study in close partnership with OAT center staff, ensuring that research tools were developed with input from those directly working with clients; b) data collection methods (semi-structured interviews and meeting notes) were designed to empower participants, enabling them to share their perspectives freely; c) we emphasized confidentiality and voluntary participation to create a safe environment for open conversation. Despite these efforts, we recognize that our roles as external researchers may have influenced participants’ responses, particularly regarding their readiness to criticize the interventions.

Interaction with participants.

Our interactions with OAT staff and clients significantly shaped the research process. As a team with expertise in mental health and public health, we knew our involvement could impact participants’ engagement with the study. Key reflections include the necessity of building trust, as participants may have been initially hesitant to share their experiences due to the sensitive nature of opioid use and mental health. Some individuals might have perceived the research team as associated with healthcare providers or policymakers, which could have affected how they framed their responses. Conducting research with individuals experiencing trauma and mental distress requires a sensitive approach. Researchers ensured that interviews were carried out empathetically, without pressuring participants to share distressing experiences.

Methodological choices and reflexivity.

The choice of a qualitative research design, which combines semi-structured interviews with participants and the analysis of staff meeting notes, was influenced by the researchers’ backgrounds in mental and public health. This approach allowed for a nuanced exploration of intervention acceptability, but we recognize certain limitations. Specifically, the thematic analysis was conducted by researchers with prior knowledge of SH+ and PM+, which may have influenced how themes were interpreted. The selection of interview questions was informed by previous research on mental health interventions, which could have shaped the types of responses elicited. The small sample size (12 participants) was a result of feasibility constraints, along with our understanding that individuals with OUD might be reluctant to engage in longer research participation. To mitigate these potential biases, the research team regularly discussed data interpretation, ensuring that emerging themes were grounded in participant narratives rather than in researcher expectations.

Interventions.

Two WHO-developed structured interventions, Self-Help Plus (SH+) [11] and Problem Management Plus (PM+) [12] were integrated into the existing OAT centers’ services at three pilot sites in Ukraine (Vinnytsia, Lviv, and Sumy) within the frame of a pragmatic trial. The SH+ and PM+ interventions have distinct features tailored to different needs. SH+ is a group-based, low-intensity stress management program based on WHO’s SH+ manual. It incorporates mindfulness and stress management techniques along with audio-visual tools to enhance delivery. In contrast, PM+ is an individual-focused intervention designed to address psychological distress and improve problem-solving skills. It includes behavioral activation, relaxation techniques, and problem-solving strategies combined with emotional regulation.

Their intended use in the Ukrainian context was twofold: (1) to support the mental health of individuals with opioid use disorder, who commonly experience elevated levels of depression, anxiety, and psychosocial instability; and (2) to provide practical coping strategies for managing the additional stressors associated with wartime conditions, such as insecurity, displacement, and disruption of daily routines.

Both interventions comprise five two-hour sessions held weekly. While SH+ is offered in a group format, PM+ is conducted individually. The facilitators for both programs are trained, non-specialist individuals working under professional supervision. The target groups for both interventions include adults experiencing psychological distress.

Facilitators who delivered interventions were professional staff, including case managers, psychologists, and nurses, with basic mental health expertise. They received structured training and supervision from senior mental health professionals, certified PM+ and SH+ trainers, and supervisors to ensure fidelity to the WHO guidelines. Adherence to the WHO guidelines was monitored using several methods. These included supervision, tracking session attendance and completion rates, monitoring dropouts, and conducting fidelity checks. Reasons for non-attendance or discontinuation were documented. Supervisors observed a subset of sessions to ensure the intervention protocols were followed correctly.

Eligibility criteria for the semi-structured interviews included such elements as: 1) participation in the OAT program; 2) presence of mental health issues (depression or anxiety symptoms) during the baseline screening; 3) confirmation of informed consent to participate in the interview; 4) participation in one of the piloted interventions: SH+ or PM+.

Participants.

Clients of OAT Programs (12 clients participated in the study). They were undergoing opioid agonist treatment and had mental health symptoms (e.g., depression, anxiety). Six participated in SH+, a group-based intervention. Six participated in PM+, an individual intervention. Clients were recruited from three OAT centers in different regions of Ukraine: Vinnytsia (Central Ukraine), Lviv (Western Ukraine), Sumy (Eastern Ukraine). Clients attended five intervention sessions and were interviewed three months after completion. They shared their perspectives on the intervention experience, engagement, and perceived impact on their mental well-being.

Participants.

OAT Staff. The study involved an OAT center staff members (4–6 per center). Staff included psychologists, social workers, case managers, and nurses responsible for delivering SH+ and PM+. They received specialized training and supervision to implement WHO interventions. Staff facilitated intervention sessions and participated in monthly staff meetings (seven in total). Provided insights into intervention feasibility, recruitment challenges, and client engagement.

Documents: Meeting Notes (N = 7). Collected from April to October 2023 during monthly staff meetings. Contained staff observations on implementation challenges, client engagement strategies, and intervention outcomes.

Documents: Interview Recordings (N = 12). Semi-structured interviews were conducted with all 12 client participants in October 2023. Recorded via Zoom, transcribed.

Events: Staff Meetings (N = 7). Monthly coordination meetings with OAT staff were held to discuss intervention progress, barriers, and adjustments.

Events: Interviews with Clients (N = 12). Conducted three months after intervention completion to assess clients’ experiences, perceived benefits, and challenges.

Acceptability of the SH+ intervention by the OAT clients.

Despite initial discomfort with the format, the SH+ intervention was well-accepted by OAT clients, primarily due to its supportive group environment and the practical self-help techniques it provided. The participants found value in the communication and emotional support within the group, as well as in the breathing and grounding exercises that they could apply beyond the sessions. This suggests that while adaptation to the intervention may take time, its long-term benefits in stress management and emotional regulation make it a valuable resource.

One key theme that emerges is the initial discomfort with the SH+ format, particularly due to the use of audio recordings and the group setting. Several participants described the experience as “strange at first” and mentioned feeling “uncomfortable the first two meetings.” However, this discomfort gradually diminished as they became accustomed to the format. The statement “SH+ was strange at first, but as I walked, I realized it worked.” highlights the process of adaptation and eventual acceptance.

Another important theme is the value of communication and support within the group. Many participants emphasized that one of the most beneficial aspects of SH+ was the opportunity to share their experiences, receive advice, and feel understood. Statements such as “I liked communicating with people that someone is worried about us.” and “Most of all, I liked the atmosphere of understanding and communication.” suggest that emotional support played a crucial role in making the intervention effective. The confidential nature of the group was also noted as a positive aspect, reinforcing trust and openness.

A third key theme is the practical application of self-help techniques learned during the intervention. Many participants reported using the breathing and grounding exercises in their daily lives. Statements such as “I remember my breathing. I do it at home, and I can calm myself down.” and “Technique, if it gets bad, then find three objects around.” indicate that these techniques were not only understood but also actively incorporated into coping strategies. The reference to “writing problems on paper and throwing them away” suggests that symbolic exercises were also impactful in helping participants manage stress.

Additionally, some participants highlighted the overall usefulness of the intervention, with several recommending it to others. Statements like “I have recommended it to many; it helps.” and “It was useful; there were moments when I had to use it.” suggest that the SH+ intervention provided tangible benefits in their daily lives.

Acceptability of the PM+ intervention by the OAT clients.

The PM+ intervention was well-accepted by OAT clients, largely due to its individual format, which fostered a sense of safety, confidentiality, and personal attention. The structured approach to skill-building, particularly in problem-solving, goal-setting, and emotional regulation, was highly valued. Participants not only learned practical coping techniques but also actively applied them in their lives, suggesting that the intervention had a lasting positive impact. The emphasis on privacy and trust in one-on-one sessions contributed to a more open and engaging experience, making PM+ a well-suited intervention for this population.

One key theme that emerges is comfort with the individual format. Unlike the initial discomfort some participants felt with the group-based SH+ intervention, PM+ was seen as familiar and reassuring. Statements such as “I liked the individual work. Listened. Communication. The atmosphere is relaxed.” suggest that participants appreciated the one-on-one format, which allowed for personal attention and open communication. The individual nature of the sessions provided a sense of control and structure, making it feel less like an obligation and more like a meaningful engagement.

A significant theme is the importance of anonymity and confidentiality. This aspect was mentioned more frequently than in SH+, indicating that participants placed a high value on privacy. The statement “Most of all, I was supported by everything being anonymous. No one will know anything about me.” underscores the reassurance that confidentiality provided. The ability to openly share without fear of judgment or disclosure appeared to be crucial for participants to fully engage in the intervention.

Another strong theme is practical skill development, particularly in problem-solving, goal-setting, and emotional regulation. Many participants highlighted the usefulness of techniques they learned, including creating schedules, setting realistic goals, and managing emotions. Statements like “The most important thing was to restrain anger.” and “I liked the fact that I was able to write functions for the day.” reflect an appreciation for structured planning and self-regulation. The ability to break tasks into achievable steps was particularly beneficial for those with physical or psychological challenges.

Emotional self-regulation and coping techniques were also widely valued. Many participants recalled learning breathing exercises, stress-relief methods, and strategies to manage depressive thoughts. Statements such as “I remember the breathing technique to control myself in stressful situations.” and “Breathing, counting to 10, and trying to distract myself with something, imagining myself at sea.” indicate that these techniques were not only taught but also actively used in daily life. The mention of “showing calendars, how to relieve stress, how to drive away depressive thoughts” suggests that participants appreciated structured guidance on managing their mental health.

Mental health prior to participation in interventions.

Answering the questions about their mental health state, clients noted that they had poor mental health, an unbalanced emotional state, a loss of meaning in life, deteriorated relationships with family, and a lack of control over their own behaviour and emotional sphere.

One dominant theme in these statements is emotional suffering and despair. The expressions of sadness and hopelessness, such as “Everything was very sad” and “I did not see the point”, suggest deep psychological distress. The statement “There was a state of a broken person” illustrates the sense of emotional defeat, indicating symptoms of depression and a loss of personal agency.

Another recurring theme is the psychological impact of war and uncertainty. The references to war, such as “Especially when the war began, it was very difficult” and “The war began, panic periodically, emotional outbursts”, reflect the distress and anxiety caused by external conflict. War creates a state of unpredictability and insecurity, which amplifies emotional struggles. The instability of the situation contributes to a constant sense of fear and panic, making it difficult for individuals to maintain emotional balance.

A significant theme that emerges is the loss of motivation and purpose. Several statements express an inability to engage in daily life activities, such as “I did not know what would happen tomorrow, I do not want to work”, and “I cannot do anything at home”. The phrase “I lived like a zombie” metaphorically represents a state of emotional numbness, where the individual feels detached from life.

Heightened anxiety and nervousness also appear as key emotional struggles. The statement “You are nervous all the time, and you have many problems all the time” indicates chronic stress, while “No matter what word you say, you begin to break down” highlights emotional fragility.

Another theme present in the statements is physical and psychological fatigue. The mention of fluctuating sleep patterns - “Then I did not want to do anything, then insomnia, then I wanted to sleep” - suggests emotional exhaustion.

Finally, social disconnection and loneliness play a crucial role in the emotional distress expressed. The statement “My son grew up and lives separately; the question is, why live?” indicates a deep sense of isolation and lack of social support. The loss of meaningful connections may intensify feelings of emptiness, contributing to the overall distress.

Mental health after the participation in interventions.

After participating in the pilot interventions, all clients, regardless of the type of intervention, noted a significant improvement in their condition, the establishment of the emotional sphere, and the harmonization of relationships with loved ones.

An important theme in these statements is regaining emotional control and stability. Several individuals mention improved emotional regulation, such as “Now I am trying to control myself”, “I normalized my emotions. Control them.”, and “I have learned to restrain myself; that is the most important thing.” These reflections highlight a conscious effort to manage emotions, suggesting personal growth in emotional resilience. Statements like “I became calmer and more controlled” and “I have become calmer, a lot.” reinforce this theme, indicating an increased ability to handle stress and emotional triggers.

Another significant theme is improved mental and physical well-being. Many statements reflect an overall improvement in health and quality of life. Expressions such as “Now I feel good. I sleep great, have a good appetite, and I do not have panic attacks.” and “Sleep has improved. I want to live.” illustrate positive changes in sleep patterns, appetite, and overall mental stability. The mention of “Before PM+, many things were different. Work, daily routine, sleep, appetite, everything is fine now.” suggests that structured support has played a key role in restoring balance in daily life.

A crucial aspect of recovery reflected in the statements is the importance of social support and communication. Statements like “My relationship with my children and wife improved.” and “My relationship with my father changed.” indicate the positive impact of emotional healing on family dynamics. Moreover, the benefits of social interactions are emphasized in “While there were meetings, it was good; the fact that I had to come was already easier.” and “When communicating, it is much easier.” These reflections suggest that structured programs, therapy, and social engagement contribute significantly to emotional recovery. However, challenges in communication persist for some individuals, as seen in “At home, the situation is such that when someone calls an acquaintance, I do not pick up the phone to avoid communicating.” This indicates that while progress has been made, social withdrawal remains a struggle for some.

A recurring theme is renewed purpose and motivation for life. Statements such as “I began to live more fully. I feel the influence; I want to live.” and “I began to look at the world differently; I wanted to live.” reveal a transformation from previous despair to a more hopeful outlook. The phrase “Everything changed a little bit after class.” suggests that structured interventions helped shift perspectives and encouraged individuals to re-engage with life. Additionally, statements like “I started setting realistic goals, which are not something that I cannot do.” indicate personal development and a focus on achievable progress.

Another important theme is coping strategies and emotional resilience. Statements such as “You will explain to me such moments that I could not even think that you can calm and control yourself with ordinary breathing and activities.” highlight the effectiveness of learned coping mechanisms. Similarly, “I know how to behave and not panic in different situations.” indicates that individuals have developed strategies to manage stress and anxiety more effectively. These insights suggest that individuals are not only recovering but also acquiring tools for long-term emotional well-being.

Challenges and strategies in client recruitment and engagement.

Recruiting clients for the SH+ group intervention proved to be a significant challenge. Staff reported that forming and engaging groups required substantial effort, as clients were initially hesitant about group participation. In contrast, Problem Management Plus was easier to introduce on an individual basis. To overcome recruitment barriers, some sites initiated SH+ groups with just 2–3 participants. Over time, as information about the interventions spread among clients, internal demand increased, and clients began actively seeking participation.

Scheduling and attendance management for SH+.

Finding suitable schedules for SH+ sessions was another key challenge, with different sites adopting various approaches. Strategies included:

• Conducting smaller groups (2–3 participants) for increased flexibility.
• Scheduling sessions early in the morning (e.g., from 07:00) to coincide with clients’ arrival for medication.
• Maintaining a stable, fixed schedule with open participation to accommodate missed sessions.
• Offering sessions at varying times to ensure accessibility for working clients.

Unstable participation due to personal circumstances also posed a challenge. A practical solution was the introduction of multiple groups on a fixed schedule, allowing participants to attend alternative sessions if they missed their designated one.

Client adaptation and participation in SH+ and PM+.

Clients initially found the SH+ group format unfamiliar, often displaying confusion during the first session. This adaptation phase was shorter in the PM+ individual format due to the direct dialogue between clients and specialists. However, by the third SH+ session, engagement and motivation significantly improved.

During SH+ sessions, facilitators needed to adapt to clients’ learning paces. When information was delivered too quickly, it was necessary to slow down, pause audio materials, and provide additional clarifications. Despite an initial recommendation of 30 participants per group, staff reported that a group size of approximately six participants was optimal, as larger groups led to distractions and reduced engagement.

Factors influencing engagement and effectiveness.

Several factors were emphasized regarding the engagement and effectiveness of the interventions. First of all, the Social Dynamics. Groups where participants knew each other (e.g., couples, friends, or partners) were more stable and engaged compared to those where members were unfamiliar. Second, the Incentives. Providing minimal encouragement, such as coffee, tea, or snacks, had a noticeable positive impact on engagement and attendance. And third, the Perceived Passivity. Clients in SH+ groups appeared passive, often not actively participating in discussions. However, they later reported practicing techniques at home, indicating that passive participation did not necessarily equate to disengagement.

Client feedback and perceived impact.

Clients’ feedback and reactions to the interventions were often discussed during the meetings: clients consistently reported positive experiences with the interventions. Many described applying learned techniques in their daily lives, and experiencing improvements in their mental well-being and relationships. Additionally, participation in these interventions increased their awareness of other available services at OAT sites, such as medical consultations, social work support, and legal assistance.

Summarizing, both interventions were perceived by staff as having unique advantages, alongside with several implementation challenges. SH+ allowed for the simultaneous engagement of multiple clients, making it a scalable option for reaching larger populations. PM+ facilitated deeper individual engagement, allowing for personalised interactions, more flexible scheduling, and better identification of client needs, including referrals for social and legal support services. Psychologists and psychotherapists found PM+ easier to implement as it aligned more closely with traditional therapeutic approaches. Additionally, PM+ enabled a more thorough assessment of clients’ psychosocial needs, leading to referrals for additional services.