This study follows a repeated measures observational design with baseline assessments, repeated measures over the course of treatment, and post-treatment assessments. Twelve to sixteen sessions of NET will be provided to all patients included in the study. Various questionnaires will be administered at baseline (T0, pre-treatment), one week after NET completion (T1, post-treatment), and 6 weeks after NET completion (T2, follow-up). In addition, assessments to measure potential processes of change will be performed at the start of each NET session. See figure 1 for a detailed overview of the planned design and administered measures.
NET will be provided by trained psychologists, psychotherapists, medical doctors, and psychiatrists. Psychologists and master’s level psychology students will perform assessments for the study. All involved professionals have extensive experience in working with migrants (in a culturally sensitive manner) and interpreters.
Figure 1: Design and overview of planned assessments
[Figure 1]
Note Biographical data: gender, age, residence status, etc.; ETI: Early Trauma Inventory- Short Form; DERS–18: Difficulties in Emotion Regulation Scale-Short Version; LEC–5: Life Events Checklist for DSM–5; PCL–5: Post Traumatic Stress Disorder Checklist for DSM–5; PCPTSD: Primary Care Post Traumatic Stress Disorder; PSS: Perceived Stress Scale; QPR–15: Questionnaire on Process of Recovery-Short Version.
Participants
The study will take place at an outpatient clinic specialized in mental health care for refugees, asylum seekers, victims of sexual exploitation, and otherwise traumatized populations in the Capital region in the Netherlands. The study aims to include 80 participants, in order to detect medium to small effect sizes [36]. Patients are referred to the clinic by a general practitioner or by a partnering social welfare organisation. Patients’ background/nationality is diverse; most originate from West Africa, the Middle East, and Eastern Europe. Their legal status varies from having obtained a residence permit or even Dutch citizenship to illegal residence in the country, and they may reside in asylum seekers centres, specialized shelters for victims of sexual exploitation, governmental shelters for illegal persons, or live independently.
Inclusion criteria
Patients will be included in the study if they are displaced victims of interpersonal violence, aged 18 years or older; if they have PTSD as a primary diagnosis established by a psychiatrist or clinical psychologist during intake; if individual NET in an outpatient setting has been indicated for them; and if they are cognitively able to give informed consent to participate in the study.
Exclusion criteria
Patients will be excluded from the study if they display signs of an acute crisis, such as acute suicidality or acute severe psychosis; or suffer from persistent substance abuse. These exclusion criteria are applied because of their expected disturbing influence on the adherence and/or completion of NET.
Recruitment
This is an ongoing treatment trial. The enrolment period is planned to run for 2,5 years from February 2018 to January 2021. Following multi-disciplinary clinical assessment and evaluation, the diagnosis and treatment indication will be discussed with patients. Those who are eligible for enrolment will be informed about the study, and will be invited to participate. This eligibility will be considered as broadly as possible within the inclusion criteria to allow for a representative sample of displaced victims of interpersonal violence. Information about the study aims and objectives, guarantee of anonymization of data and the fact that participants are free to terminate participation at any moment, will be given orally and provided on paper through an information leaflet. After intake patients are placed on a waiting list for NET, ranging from one to four months. When patients from the waiting list are invited to start NET, they will once again be informed about the study orally and on paper. Patients will be asked to consider participation over a minimum period of three days. Afterwards they will be contacted by phone or face-to face, and given ample opportunity to ask additional questions. If they indicate willingness to participate in the study, an appointment is made to sign informed consent, and conduct the baseline assessment (T0). Participants are invited to bring someone they trust to this meeting. Participants will be receiving a voucher of 10 euros after the follow-up measurement. If after the first year the aspired total number of participants seems unachievable, prolongation of the enrolment period, and multicentre options will be explored after consultation with the involved medical ethical committee.
Intervention
Narrative Exposure Therapy
NET is an evidence-based short-term psychotherapy targeting PTSD symptoms, specifically appropriate for multiple trauma in divergent cultural settings. For the study population in question the method is found to be feasible [37], and is considered the first choice TFT [34]. The NET protocol includes 12–16 sessions of individual trauma focused exposure, performed weekly or twice a week by trained mental health professionals. Each session lasts 90–120 minutes, depending on the content of the trauma which is targeted during the session, and the possible involvement of an interpreter. NET aims to create a chronological narrative of a patient’s life story, including both traumatic and empowering memories. During each session one or more significant memories (traumatic or empowering) are discussed in great detail. Imaginary exposure, meaning-making, and reprocessing are used to reduce PTSD symptoms. An account of each session is written down by the therapist, which will result in a patient’s biography when the therapy has been completed.
Co-interventions before and during treatment
When participants cannot immediately start NET, there are no restrictions in psychological or pharmacological interventions received during their waiting period, applied in accordance with national guidelines. Such interventions can be indicated either for symptom management or as a preparation of individual TFT. In addition, individual sessions can be provided in case of (imminent) crisis. From the start of NET onwards, however, no other modules will be provided, unless in case of acute crisis in which the safety of a participant is endangered or he/she is about to harm others. Previously started pharmacological interventions can be continued during NET, however no new pharmacological interventions will be started during NET.
Discontinuation of the intervention and drop-out
Discontinuation of NET will take place if patients so wish or if multi-disciplinary clinical evaluation indicates that continuation is not in the best interest of the patient. If patients wish to stop participating in the study but wish to continue NET, this will be allowed. Patients will be considered dropouts when there are deviations from the NET treatment protocol for more than four consecutive sessions (i.e., no trauma-focused approach during the sessions or no-show), since in these cases the effectiveness of the treatment offered cannot be assured [35].
Measurements
Perceived Stress Scale (PSS)—full scale administered pre-and post-treatment
The PSS [38] has been developed to measure the perception of daily stress by assessing how unpredictable, uncontrollable, and overloading patients experience daily life. With 10 items, thoughts and feelings, and the evaluation of daily life in the last month are explored through a 5-point scale ranging from 0 to 4. Mean scores will be calculated, ranging from 0 to 4. Example item: “In the last month, how often have you been upset because of something that happened unexpectedly?” Administration of the questionnaire takes approximately 10 minutes. Acceptable psychometric properties of the instrument have been established [39].
Subscale administered before each session
The four items version of the PSS [40] will be administered at the start of each session. These items have proven sensitivity to short term changes in stress [41]. For the purpose of this study the indicated timespan was changed from ‘In the last month’ to ‘In the last week’ to match the other pre-sessions measures for possible predictors.An example item is: “In the last week, how often have you felt that things were going your way?” These items will be scored on a VAS-scale of exact 10 centimetres by placing a cross on a line from 0 (not at all) to 100 (completely). Mean scores will be calculated, ranging from 0 to 100.
Difficulties in Emotion Regulation Scale short version– 18 (DERS) - full scale administered pre- and post-treatment
The DERS was developed to measure emotion regulation. The DERS–18 comprises 18 items, and uses a 5-point Likert scale ranging from 1 to 5; it has 6 subscales: nonacceptance of emotional responses; difficulty engaging in goal-directed behaviour; impulse control difficulties; lack of emotional awareness; limited access to emotion regulation strategies; and a lack of emotional clarity. Mean scores will be calculated, ranging from 1 to 5. Example item: “I pay attention to how I feel”. Administration of the questionnaire takes approximately 10 minutes. The DERS has high internal consistency, good test-retest reliability, moderate construct, and predictive validity [42].
Subscale ‘impulsivity’ administered before each session
As a proxy of emotion regulation the subscale ‘Impulsivity’' will be used, comprising three items from the ‘Difficulties in Emotion Regulation Scale’ (DERS–18; 40). For the purpose of this study the phrase 'In the last week I have felt:’ was added to match the other pre-sessions measures for possible predictors.Example item: “When I am upset, I become out of control”. Items will be scored on a VAS-scale ranging from 0 (not at all) to 100 (completely). Mean scores will be calculated, ranging from 0 to 100.
PTSD Checklist for DSM–5 (PCL–5) - administered pre-and post-treatment
The 20 item PCL–5 is a self-report checklist which measures the presence and severity of the 20 DSM–5 symptoms of PTSD on a 5-point scale (0–4) (e.g., “Trouble remembering important parts of the stressful experience”). Mean scores will be calculated, ranging from 0 to 4. It will be used to indicate PTSD symptom severity pre- and post-treatment. Administration of the questionnaire takes approximately 10 minutes. The instrument has good psychometric quality [43].
Primary Care Posttraumatic Stress Disorder (PCPTSD)- administered before each session
Because a short version of the PCL–5 is unavailable, the five-item Primary Care Posttraumatic Stress Disorder (PCPTSD) checklist was selected to increase the feasibility of the frequently repeated measurements. This questionnaire is used to measure PTSD symptoms [44]. For the purpose of this study the indicated timespan was changed from ‘In the past month, have you’ to ‘In the last week’ to match the other pre-sessions measures for possible predictors.An example item is: 'In the last week did you have nightmares about the event(s) or thoughts about the event(s) when you did not want to?” These items will be scored on a VAS-scale ranging from 0 (not at all) to 100 (extremely). The questionnaire has good psychometric qualities [42]. Mean scores will be calculated, ranging from 0 to 100.
Mood- measured before each session
Mood will be measured using a validated single item measure [45]. For the purpose of this study we have altered the item 'At the moment I feel’ to ‘In the last week I felt’ to make the timespan congruent to the other pre-session measures for possible predictors. This mood item will be scored on a VAS-scale ranging from 0 (sad) to 100 (happy). Mean scores will be calculated, ranging from 0 to 100.
Critical incidents
Before each therapy session the client will be asked to report if any relevant personal circumstances have arisen since the last appointment.
Other
Biographical data of patients will be collected (i.e., gender, age, educational level, current residence, legal status, country of birth) to describe the study population.
Questionnaire on Process of Recovery Short Version—15 (QPR)
The QPR is a 5-point scale (0–4), self-report questionnaire that probes people’s recovery and meaningful aspects in the recovery process (e.g., “I feel able to take chances in life.”).”). The QPR–15 consists of 15 items. Mean scores will be calculated, ranging from 0 to 4. The questionnaire has good psychometric properties, and has proven to be associated with quality of life, empowerment, and psychological wellbeing [46]. Administration of the questionnaire lasts approximately 20 minutes. The questionnaire has been selected because it represents psychological wellbeing beyond the scope of mental health symptoms. The QPR is reliable and valid, and has proven to be associated with quality of life, empowerment and psychological wellbeing [46].
Early Trauma Inventory—short version (ETI-SF)
The ETI-SF was developed to determine potentially traumatic events before and after the age of 18 years old [47]. The ETI-SF comprises 27 items, that assess physical, emotional, and sexual abuse. Items vary between open questions and multiple choice being answered with yes or no. The scale has a range from 0 to 29, with higher scores referring to a higher number of traumatic experiences. Administration of the questionnaire lasts approximately 10 minutes. Its reliability and validity are good [48]. The questionnaire has been selected to describe trauma-related features of the study population.
Life Events Checklist (LEC—5)
The LEC–5 comprises 17 multiple choice items on a 6-point nominal scale (i.e., ‘happened to me’; ‘witnessed it’; ‘learned about it’; ‘part of my job’; ‘not sure’; ‘doesn’t apply’). The checklist aims to determine whether someone has ever been exposed to 16 events known to potentially result in PTSD or distress, and one additional event not captured in the first 16 items. In the last part of the LEC–5 respondents are asked which event he/she considers to have had the most impact, followed by 7 questions, both open- and multiple-choice questions, aimed at identifying the characteristics of this event. The scale has a range from 0 to 68, with higher scores referring to a higher number of traumatic experiences. Administration of the questionnaire lasts approximately 20 minutes. The reliability of the LEC–5 is considered to be good [49]. The questionnaire was selected to describe trauma-related features of the study population.
Data collection, management, and analysis
Procedure pre-session measures
During baseline (T0) and at the start of each TFT session the patient’s fixed practitioner or a supervised master’s level psychology student will administer the thirteen items selected to assess the four abovementioned possible predictors. To avoid an order effect, the sequence of the measures for possible predictors and the order of questions within every measure will change with every session. These measures will only be administered during the treatment period. They will be administered by pen and paper, and are expected to take on average 10 minutes. Questionnaires are translated from their original English version according a forward-backward procedure by two independent native speakers into Dutch, and by professional translators into Arabic, French, Amharic, and Tigrinya. Interpreters will assist for other languages.
Procedure pre- and post-treatment
During baseline (T0), post-treatment (T1), and follow-up (T2) measurements, the abovementioned set of questionnaires will be administered. See figure 1 for a detailed overview of the planned time points for assessments. These questionnaires will be administered digitally, and are expected to take a maximum of 80 minutes. Questionnaires are available in Dutch and English. Given the lack of computer skills and the often limited Dutch and/or English proficiency within the study population, a clinician and interpreter will be available for assistance. Measurements will take place at the treatment location; if preferred, this meeting will be combined with other appointments. After the last assessment participants will receive a voucher of 10 euros.
Statistical analysis
First, multiple regression analyses and logistic regression analyses will be performed to examine whether high perceived daily stress, emotion dysregulation, and low mood at baseline predict drop-out, no-show, and treatment outcomes. Secondly, the concurrent association between each possible predictor measured prior to each session (i.e., perceived daily stress, emotion regulation, and mood) and PTSD symptoms will be examined using bivariate (multilevel) growth modelling, as multiple observations of the predictor variables and PTSD symptoms (level 1) are nested within individuals (level 2) [50]. In order to infer that change in the predictor variables leads to change in PTSD symptoms, we will examine the time-line (i.e., temporal precedence) in two ways [51, 52]. The dynamic (i.e., temporal) associations will be examined by estimating whether change in PTSD symptoms from the previous week to the current week (t) can be predicted by change of a possible predictor at the previous week (t–1) using multilevel modelling. To examine the time-line of larger shifts instead of week-to-week changes, it will be examined whether the earliest significant decrease in mean levels of each possible predictor (improvement) occurs before the largest reduction in mean levels of PTSD symptoms.