The Effectiveness and Cost-Effectiveness of Attachment Based Family Therapy for Young Adults with High Suicidal Ideation: Protocol of a Randomized Controlled Trial.

The Effectiveness and Cost-Effectiveness of Attachment Based Family Therapy for Young Adults with High Suicidal Ideation: Protocol of a Randomized Controlled Trial. | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article The Effectiveness and Cost-Effectiveness of Attachment Based Family Therapy for Young Adults with High Suicidal Ideation: Protocol of a Randomized Controlled Trial. Claudi L. Bockting, Guy Bosmans, Nele Bergers, Luana Gavan, Mickaël Hiligsmann, and 5 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-4518344/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 16 Oct, 2024 Read the published version in Trials → Version 1 posted 5 You are reading this latest preprint version Abstract Young adult suicidality is worldwide a prevalent mental health problem and the number one cause of death, with devastating consequences for individuals and their families, and substantial economic costs. However, psychological and pharmacological treatments currently recommended in guidelines for treatment of high-risk youth for fatal suicide have limited effect. In line with the WHO’s recommendation to involve the family in treatment of these youth, Attachment Based Family Therapy (ABFT) was developed; a 16-week attachment and emotion-focused treatment, implemented in mental health care settings across various European countries in the past years, and is becoming increasingly popular among therapists. However, the (cost-)effectiveness of ABFT has not been studied in emerging adults. In the proposed pragmatic RCT we aim to evaluate the effectiveness and cost-effectiveness of ABFT compared to Treatment As Usual (TAU) on suicidality, as delivered in daily practice. This pragmatic multicenter study in the Netherlands and Belgium includes 12 participating sites. Participants are suicidal young adults (≥ 31 SIQ-JR score) between 18 and 25 years old who seek mental health treatment (n = 142) and their caregivers. The primary outcome is suicidality (SIQ-JR), with assessments at baseline, post-intervention (five months after baseline), three, six and twelve months after intervention. We predict that, compared to TAU, ABFT will lead to a stronger reduction in suicidality and will be more cost-effective, over the course of all timepoints. We also expect stronger decreases in depressive symptoms, given that suicidality is very common in individuals with depressive disorder, as well as more improvement in family functioning, autonomy, entrapment, and young adult attachment, in the ABFT condition. This study can contribute to improving the care for suicidal youngsters with high mortality risk. Treatment of suicidal emerging adults is understudied. The results will inform clinical guidelines and policy makers and improve treatment of suicidal emerging adults. Figures Figure 1 Administrative information This study protocol follows the SPIRIT reporting guidelines (Chan et al., 2013). The SPIRIT Checklist can be found in the Supplementary Materials and offers an overview of where specific information can be found within the article. Trial Status and Protocol version: First approved protocol version in the Netherlands: Version 3, date May 8, 2023 Latest approved protocol version in the Netherlands: Version 8, date February 2, 2024 Start of recruitment: October 5, 2023 Current status: Recruitment ongoing Approximate date of recruitment completion: May 2025 Roles and responsibilities – Contributorship: Claudi Bockting, Guy Bosmans, and Nadia van der Spek designed the RCT, and drafted the initial research protocol. Ben Wijnen and Joran Lokkerbol designed and wrote the statistical analysis and cost-evaluation section, with considerable input from Mickaël Hiligsmann and Geert Molenberghs. Derek de Beurs contributed to the initial design of the RCT and to the research protocol. Nele Bergers, and Luana Gavan helped revising the original research protocol and contributed to writing the final version of the manuscript, together with Nadia van der Spek and Claudi Bockting. Nadia van der Spek, Nele Bergers, Luana Gavan, Claudi Bockting are Guy Bosmans are currently coordinating the study. All authors gave feedback on the final manuscript version and approve the final version. Roles and responsibilities – Sponsor and funder: This work was funded by ZonMw and the Belgian Health Care Knowledge Centre (KCE), as part of the BeNeFIT (Belgium-Netherlands Funding of International Trials) programme. Roles and responsibilities – Committees: Several stakeholders participate in the Trial Steering Committee together with the research team and the funder Benefit. These are patient organisations Stichting Zelfbeschadiging, Depressievereniging, Ups & Downs, suicide prevention organisations 113online and VLESP. Introduction Emerging adult suicide is a serious problem around the world. Suicide is estimated to be the first to the fourth cause of death in the 15-29 years age group (WHO, 2021; CBS, 2020). Moreover, for each fatal suicide, approximately 20 non-fatal suicide attempts have been registered (WHO, 2014). Identifying and treating ultra-high suicide risk youth is one of the pressing current challenges in societies across the world (U.S. preventive service task force, 2022). The emotional cost for families and loved ones cannot be measured, but is clearly devastating. In addition, the economic and societal cost of fatal suicide is very high, and includes medical costs for individuals and families, lost income for families, and lost productivity for victims and family members (Shepard et al., 2015; Doran & Kinchin, 2020). Suicidal ideation is very prevalent among people with mental health disorders, such as depression (De Beurs et al, 2019). Suicidal ideation can result in suicide attempts and fatal suicide, but is in itself also very burdensome for individuals (Jaffe et al., 2019; Klaufus et al., 2022). The societal and economic burden of patients with suicidal ideation is higher compared to depressed patients without suicidal ideation (Benson et al., 2021). Therefore, suicidal ideation needs to be targeted with treatment. However, research on the treatment of youth suicidality lags significantly behind. Current treatments, including pharmacological treatment of suicidal emerging adults, have limited effects (Tondo & Baldessarini, 2016; Franklin et al, 2017). Treatment programs that can successfully treat emerging adults at high suicide risk are greatly needed and the societal impact of providing cost-effective treatment could be significant. Thus, tackling psychological mechanisms in treatment that contribute to decreasing young adult suicidality and depression is a critical next step to tackle suicidality. Until recently, standard treatment of suicidality consisted of cognitive behavioural therapy (CBT), dialectical behavioural therapy (DBT), and/or medication, but all showed limited effects on suicidality (Glenn et al., 2015; Fox et al., 2020; Franklin et al., 2017). Even worse, a recent meta-analysis of 50 years of treatment research found that the effect of existing treatments only produces small effects on suicidal behaviour (Franklin et al., 2017). A recent review (Asarnow & Mehlum, 2019) shows that there is only a limited number of evidence-based treatment options for adolescents that all only have limited treatment effects on suicidality, calling for more trials specifically targeting suicidality. Mixed support for the current treatments has contributed to the general recommendation to provide psychological treatments aimed at improving family relationships (Merelle et al., 2020; WHO, 2018). Family therapy is a less explored treatment option for suicidality. There is increasing evidence that points at the importance of working with families and addressing the unmet need for belonging and perceived burdensomeness when targeting youth suicidality (Asarnow & Mehlum, 2019; Merelle et al., 2020; Joiner et al., 2002, 2005, 2009). Even for emerging adults, who are in a developmental phase of striving for autonomy, not addressing family conflict might exacerbate the problem or inhibit the family from being a source of support for the patient (Devacht et al., 2019). In most cases, these emerging adults will either be living at home or be dependent on their families. The WHO recommends to involve the family in the treatment of suicidal youth as a powerful way to treat suicidality (WHO, 2018). One program that has been developed to specifically target suicidal youth, and that specifically focuses on the family, is Attachment Based Family Therapy (ABFT; Diamond et al., 2010, 2016, 2019). ABFT is a promising intervention for adolescents, gaining popularity around the world, that involves both the youngster and the caregivers. ABFT uses family therapeutic techniques to restore attachment relationships between members as a strategy to decrease youngsters’ levels of depression and suicide risk (Diamond et al., 2016). Multiple studies have shown high acceptability and feasibility of ABFT for both adolescents and emerging adults (DeVacht et al., 2019; Diamond et al., 2022; Van der Spek et al., 2023; Santens et al., 2018; Santens et al., 2020). However, effectiveness studies have shown mixed results on suicidal ideation (Diamond et al., 2002, 2010, 2019; Waraan et al., 2021). Moreover, a recent meta-analysis on the RCTs up until now has shown no effect of ABFT on suicidal ideation among adolescents (Schulte-Frankenfeld et al., submitted). ABFT has never been studied in an RCT among emerging adults, who are in a developmental phase characterized by a different type of parent-child relationship. Therefore, more research is needed to establish whether ABFT is a cost-effective treatment for suicidal ideation and to investigate its effectiveness for emerging adults, instead of adolescents. The current RCT will compare ABFT added to treatment as usual (ABFT + TAU) to TAU alone among emerging adults between 18 and 25 years old, with high levels of suicidal ideation, receiving care in mental health care facilities in the Netherlands and Belgium. The main goal of the study is to assess the effectiveness and cost-effectiveness of ABFT added to TAU, compared to TAU alone, on suicidality in emerging adults over the course of five time points (baseline, post-treatment, three, six, and twelve months follow-up). Secondly, the effects of ABFT on depression, self-injury, entrapment, autonomy, family functioning, and young adult attachment will be investigated. Methods/Design Design This study is a randomized controlled pragmatic multi-center trial comparing Attachment Based Family Therapy (ABFT) added on to Treatment As Usual (TAU). Participants are suicidal emerging adults between 18 and 25 years old, who seek treatment, and their parents or caregivers. The study will take place in 12 mental health care centers in the Netherlands and Belgium where suicidal patients are treated, including both inpatient and outpatient clinics, academic and non-academic treatment centers, and private practices. A list of all participating study sites can be found in the Supplementary Material. After regular intake procedures in the treatment facility, patients with suicidal ideation and their caregiver(s) will be informed about the study and asked to participate by a local researcher. After at least one week, the participants who are willing to participate, sign informed consent and will be screened on in/exclusion criteria by a researcher trained in the study protocol. Eligible patients and their parents/caregivers will be included in the study. After completing the baseline assessments, they will be randomized to ABFT+TAU or TAU alone. Follow-up interview assessments will take place post-intervention, at three, and at 12 months, by a researcher blinded to the treatment condition. Questionnaire assessments are administered at baseline, post-intervention, and at three, six (brief assessment for young adult only), and 12 months after intervention. Suicide attempts are registered during the interview assessments, and in the questionnaires for the youngster. As long as the participant is in treatment at the site, suicide attempts will be reported by the therapist. For more detailed information, see Figure 1. Study sample Inclusion criteria are: a) between 18 and 25 years old, b) a score above the cut-off of the Suicidal Ideation Questionnaire Junior (SIQ-JR) (≥31) and c) at least one parent or primary caregiver that participates in the assessments and treatment. This could be a biological parent, stepparent, grandparent, other relative, or a foster parent. Exclusion criteria are: a) Other DSM-5 disorders: severe alcohol or cannabis use disorder, for all other substances: moderate or severe substance use disorder, conduct disorder, evidence of psychotic features or prior psychosis; b) severe cognitive impairment (e.g., mental retardation, severe developmental disorders) as evidenced by educational records, parental report and/or clinical impression; c) other circumstances that might affect participation (e.g., severe medical disorder, relocation). Sample size calculation: A recent meta-analysis, including three RCTs on ABFT for suicidal patients, found a Cohen’s d of 0.4 (Schulte-Frankenfeld et al., submitted). Based on this estimated effect size (Cohen’s d = 0.4), focused on the primary outcome (suicidality) and the proposed statistical analyses (i.e. Linear Mixed Modelling with five complete assessment time points), a base correlation across the 5 measurement of .5, an interclass correlation of patients 'nested' in clinicians of .05, and assuming a design effect of 1.24 (given the clustered design), we will be needing ≈46 participants per arm for a power of 80% and a nominal type I error of 0.05 to be able to show a medium effect of ABFT. Based on previous trials (Diamond, 2010, 2019), we estimate a 35% drop-out rate. We will therefore need a sample size of 71 ((46)/(1-0.35)) respondents per arm, resulting in a total of 142 participants. Recruitment strategies: Participants will be recruited from the participating study sites by approaching them after intake or by searching for potential candidates in the existing caseload of therapists. Staff at the participating study sites have been informed about the study and can refer patients to the local study coordinator. The study will also be promoted via other channels such as personal network, news outlets, contact with suicide prevention organizations and general practitioners, as well as presence at relevant congresses and conferences, as a way to increase awareness about the study and reach the target sample size. Randomization and stratification Eligible patients that gave informed consent, who are included in the study, will be randomized after baseline, through block randomization. A computer-generated randomization table with random block sizes will be prepared by an independent researcher not involved in the study. We will stratify on one variable: the number of previous suicide attempts (0 or >0). Stratification will be done per country, in order to maintain balanced treatment conditions across both countries. The result of the randomization procedure will be sent to the main study coordinator, who will then communicate it to the local principal investigator at the study site. The local principal investigator, who has been trained in the study protocol, is responsible for assigning participants to the correct therapist on the basis of the randomization outcome. Blinding and unblinding Only the researcher performing the follow-up interview assessments will be blinded to the treatment condition. Should unblinding occur inadvertently, then a different researcher will be assigned to perform follow-up assessments for that specific participant. Cases of unblinding during the interview assessment (e.g., the participant mentions their treatment condition to the interviewer) will be documented in a protocol deviation log. Intervention: Attachment Based Family Therapy (ABFT) (Diamond et al., 2014) is a manualized treatment including 16 sessions, that emerges from interpersonal theories that suggest suicide can be precipitated, exacerbated, or buffered against by the quality of family relationships. ABFT is delivered by licensed clinical psychologists, psychotherapists, or psychiatrists who received nine days of training and 20 hours of supervision in ABFT. Although ABFT therapists implement behavior-focused and psychoeducational interventions, the model is primarily a process-oriented, emotion-focused treatment, guided by a semi-structured treatment protocol. Suicide risk is monitored in every session by the therapist. Treatment is organized around five specific tasks, each with a distinct process and goal. Each task refers to a specific treatment goal and offers a principle-driven guideline to achieve each goal. Task 1 (relational reframing) focuses on shifting the family's treatment goal from “fixing the young adult” to improving family relationships. The Task 1 session includes a discussion of what prohibits the youngster from turning to his or her parent(s)/caregiver(s) for help when feeling so hopeless and distressed, that they contemplate suicide. Family barriers range from: stress due to the youngster’s symptoms, history of negative interactions and communication, abuse, neglect, abandonment and/or parental psychopathology. Even well-functioning families need help effectively managing youth’s suicidality. Task 2 (alliance building with the youngster, three to four sessions) aims to help the youngster gain a better understanding of how ruptures in trust with the parents contribute to conflict and emotional distance. Emerging adults are then motivated and prepared to discuss these ruptures with their parents. Task 3 (alliance with the parents, three to four sessions) aims to help the parents become more empathic and sensitive to the youngster’s emotional needs. Task 4 (the attachment task, three to four sessions) brings all the family members back together to discuss some of the issues and ruptures that were identified in Tasks 2 and 3. ABFT considers caregiver support in response to the youngster's shared experiences as a corrective attachment experience that helps repair trust. Task 5 (promoting autonomy) assumes that task 4 has built up enough trust that the parents can once again serve as a secure base to support the young adult’s competency and autonomy development. These five tasks provide a scaffold to guide the treatment. For this trial, we made a few adjustments to the treatment manual. First, at the beginning of the treatment, a family-oriented safety plan will be made for all patients receiving ABFT and will be used at all times during treatment when the patient is at high risk. Second, the developmental task of emerging adults, which involves obtaining autonomy and launching into adulthood, is central in the treatment. For instance, the Task 1 session is not mandatory if the young adult prefers to start with separate sessions. Task 4 is still about discussing ruptures, but also focuses on self-expression and individuating from the parents. No other treatment modifications will be performed. The possibility of discontinuing the allocated intervention will be discussed within each study site and with the participants’ main therapist, taking into account participants’ wishes and any safety-related concerns. Therapists will receive supervision over their cases in the study. All ABFT sessions will be videotaped and a randomly selected 15% of the tapes will scored by an independent rater to score treatment fidelity. Treatment fidelity will be assessed with the Therapist Behavior Rating Scale-3 (TBRS-3; Diamond, Hogue, Diamond & Siqueland, 1996). The TBRS-3 items demonstrated reliability with ICCs ranging from good (.69) to excellent (.96). Treatment as usual (TAU) Participants in both arms will receive TAU, in the experimental condition ABFT will be delivered as an add on. Most treatment centers’ clinical practices rely heavily on the use of antidepressants and/or cognitive behavioral therapy (CBT) or dialectical behavior therapy (DBT). All regular interventions are allowed in TAU, except for systemic family therapy of more than 4 sessions in the first five months of the study (i.e. a family therapy session is defined as a contact of 30 minutes or longer with a family member or caregiver present). Parental involvement is generally part of treatment as usual, and can comprise for instance psycho-education, parental support, or skill training. We will monitor what TAU entails. TAU is not a comparator in this trial, as the trial aims to investigate whether ABFT is (cost-) effective as an add on to TAU, and not whether it is more effective than TAU. Eligibility screening: After signing informed consent, the eligibility will be assessed in a pretreatment session, using the SIQ-JR, the SCID-5-S interview, and patient records. Suicidal Ideation Questionnaire Junior (SIQ-JR, Reynolds & Mazza, 1999), assesses suicidal ideation in youth in the past month. The SIQ-JR is a 15-item questionnaire, and has been used in many clinical studies. It forms a continuum ranging from thoughts of death and wanting to be dead, general and specific suicidal plans, preparations for/and actual suicide attempts. Eligible participants need to score above the cut-off of 31, which indicates potentially serious risk for suicide. The measure was found to be internally consistent (a = .94) with a test-retest reliability of .89 over three weeks. Participants indicate the frequency of certain ideations and behaviors in the past month, and respond to items like “I have thought about killing myself” on a 7-point Likert scale (0 not in the past month, till 6 almost every day in the past month). An extra item was added to assess suicide attempts (“I have tried to kill myself in the past week” (yes/no)). In case of a (fatal) suicide attempt, the highest SIQ-score will be given at that timepoint. The exclusion criteria will be assessed using the SCID-5-S interview . The SCID-5-S is designed as a semi-structured diagnostic interview for making the major DSM-5 diagnosis. Validation and reliability studies have been done on the SCID-S versions DSM-V, DSM-IV and DSM-III-R (Osorio et al, 2019; Lobbestael et al., 2011; Zanarini et al., 2000; Martin et al., 2000; Ramirez Basco et al., 2000; Fenning et al., 1994b, 1996; Zanarini & Frankenburg, 2001; William et al., 1992; and Skre et al., 1991). The results of these studies show that the validity and reliability of the SCID-S was good. The SCID-5-S can be administered effectively (mean 18.7 ± 11.6 minutes, median 15 minutes). Clinicians can use it after a brief training session. Baseline only Socio-demographic factors and participant characteristics and Childhood trauma using the Childhood Trauma Questionnaire (CTQ; Garnefski & Kraaij, 2001). This is a self-report 28-item questionnaire that measures 5 types of maltreatment: emotional, physical, and sexual abuse, and emotional and physical neglect (Garnefski & Kraaij, 2001). We include this questionnaire at baseline only, since childhood trauma is an important predictor of suicidality and depression. This questionnaire is not time-specific. Outcomes Primary outcome : Change in suicidal ideation and behaviour as assessed by the Suicidal Ideation Questionnaire Junior (SIQ-JR; Reynolds & Mazza, 1999, see description above) in the young adult from baseline to post-intervention, three-, six- and twelve-months follow-up. Secondary outcomes: Suicide attempts and suicidality will be additionally investigated using the Structured Clinical Interview DSM 5 (SCID-5-S; Michael B. First, JBWW, Lorna Smith Benjamin, Robert L. Spitzer, 2017). Entrapment will be assessed using the Entrapment Short-Form Scale (E-SF; De Beurs et al., 2020). The E-SF is a 4-item questionnaire, which will be administered for the young adult only. Respondents are asked to respond to statements on internal and external entrapment on a 5-point scale. Correlations between the sum of these four items and the 16-item full Entrapment Scale (Gilbert & Allan, 1998) were nearly perfect (0.94 for the clinical sample and 0.97 for the population-based sample). Non-Suicidal Self-Injury (NSSI; Buelens et al.2020). This is a self-report 5-item questionnaire that measures non-suicidal self-injury and will be administered for the young adult only. Depressive symptomatology as assessed by Patient Health Questionnaire (PHQ-9; Kroenke, Spitzer & Williams, 2001) . The PHQ-9 is recommended in the core outcome set for depression and represents the outcomes that matter most to patients with depression. It is a 9-item questionnaire, demonstrating good reliability and responsiveness to change, with Cronbach’s alphas ranging from 0.82 to 0.92 (Cameron et al., 2008), and will be administered to the young adult only. World Health Organization Disability Assessment 2.0 (WHODAS 2.0; Üstün et al., 2010), is part of the core outcome set for depression, consisting of 12 items covering the domains of Cognition, Mobility, Self-care, Getting along, Life activities and Participation. The WHODAS is a questionnaire with good validity and reliability (Üstün et al., 2010), and will be administered to the young adult only. The Self Report Measures of Family Functioning (SRFF; Stark et al., 1990) is composed of 15 five-item factors measuring family functioning (e.g., cohesion, conflict, and democratic family style) with Cronbach's alphas ranging from .63 to .91, with most in the .70 to .85 range. Analyses have yielded highly reliable and stable factors (Stark et al., 1990). We will administer the SRFF to the young adult as well as the parents. Young adult attachment: To measure secure attachment in the young adult, we will use the Secure Base Script Task (SBS;Waters & Waters, 2006). This is a narrative task during which participants need to construct stories (six items for six stories) with prompt words that loosely suggest a secure base script, due to participants who know the script cannot suppress telling secure base script stories. This measure correlates highly and significantly ( r = .50) with attachment interviews that are considered valid in the field of attachment research (Waters et al., 2019; Waters & Roisman, 2019). Autonomy of the young adult , as assessed by the questionnaire My Parents and I (Van Petegem, 2008), a combination of items of the Emotional Autonomy Scale (EAS; Steinberg & Silverberg, 1986) and the Psychological Separation Inventory (PSI; Hoffman, 1984), will be administered for the young adult only. The reliability of the combined scales, indicated by Cronbach's alpha, amounts to .84. Childrens Depression Inventory second edition (CDI-2, Bodden et al., 2016) The CDI-2 for parents consists of 17 items, scored on a 4- point Likert scale to indicate how often in the past two weeks symptoms occurred in their child. They respond to statements like “Looks sad” (0=not at all, 1=sometimes, 2=often, 3=almost always). A CDI-2 cut-off score of 16 is indicative of “significant” depressive symptoms according to the Dutch Mental Health Care guideline (Buitelaar et al., 2009: Multidisciplinaire Richtlijn GGZ, Addendum Depressie bij Jeugd, 2009) Cost-effectiveness Health care and associated costs and costs from productivity loss (TiC-P; Hakkaart-Van Roijen, 2002). The TIC-P is a questionnaire assessing participants’ healthcare resource use and productivity losses, including school and work drop out. The TIC-P will be administered at every measurement point and will inquire about healthcare resource use and productivity losses since the previous measurement (and in case of baseline for the three months prior to baseline). The TIC-P will be administered to the emerging adults only. Health-related quality of life (EQ-5D-5L; Bouckaert et al., 2021; Versteegh et al., 2016). The EuroQOL five dimensions (EQ-5D) is a short questionnaire used to assess utilities of the young adult at each measurement. Utilities are converted into Quality-Adjusted Life Years (QALYs), using Dutch and Belgian tariffs. During-treatment assessment every two months Working Alliance Inventory (12-item WAI; Horvath & Greenberg, 1986). The WAI measures overall therapeutic alliance and consists of subscales measuring (quality of therapy) tasks, goals and bonds. This measure has strong psychometric properties and has been used widely in psychotherapy research (Tracey & Kokotovic, 1989). Therapy Procedure Checklist (TPC, Weersing et al., 2002). The TPC is developed to assess therapists' reports of the techniques they employ when working with child and adolescent clients, and will be used to monitor TAU in both study arms. TPC items encompass the three most common therapeutic models for youth: psychodynamic, cognitive, and behavioral. TPC scales have good internal consistency (all alpha > .86) and test-retest reliability (all r > .79) across samples. Data collection and data management: Data will be collected through questionnaires (using the clinical research platform Castor Electronic Data Capture) or (clinical) interviews. All data will be collected by researchers either from the study site or the sponsor, who have been trained in the study protocol, procedures and assessments. An electronic CRF (Castor) is used to collect a part of the data, a copy of the blank CRF pages is kept as back-up. Some data will be collected through a CRF on paper and will be entered in Castor afterwards. Access to the data collection system is based on individual login and access rights are only given to authorized staff. For each study-specific data collection, source documentation is available. Budget is allocated both for storage during the study as well as for archiving upon completion of the study. Budget is allocated for data management activities and creating a FAIR dataset. Retention: Participant retention will be promoted by sending regular reminders for completion of assessments both by researchers. Participants are also encouraged to complete all follow-up assessments by receiving a monetary incentive. Participants who decide to discontinue treatment can continue to participate in the study. If participants decide to discontinue study participation, they can continue treatment without any additional consequences. An early termination assessment will be done for participants who decide to discontinue participation. Data processing and statistical analysis: The data will be stored in a generic and machine actionable format, i.e. SPSS, R or excel. The acquired data will be stored as read-only file and a new file will be created for further processing and statistical analysis. All data processing and analysis will be programmed in syntax or script files. Descriptive comments will be added to the syntax or script files. Data sets and syntax or script files will be placed under version control. Data corrections in this phase will be programmed in syntax or script files. With regard to sharing data for processing or statistical analysis, data will transfered in a secure way. Encoded data from participating sites will be collected using secured links or during a site visit. Statistical analyses: All analyses will be performed blind by an independent researcher on the intention-to-treat sample. As per the CONSORT statement, baseline data will be presented by presenting mean and standard deviations for continuous variables (or median and a centile range when asymmetrically distributed) and by using numbers and proportions for categorical variables. Quantitative outcome measures will be analyzed using Linear Mixed Modelling, using all five assessment time points of the primary outcome measure. A similar (but Generalized) approach will be applied to estimate the impact on secondary outcomes. Our data, which is expected to contain missing values due to dropout, can be analyzed under the relatively relaxed assumption of missingness at random using linear mixed modelling (Verbeke & Molenberghs, 2000; Molenberghs & Kenward, 2017). Mixed modelling will be used to evaluate the impact of condition (ABFT vs TAU) on SIQ-JR scores over all five measurements with participant ID as random effect. The fixed part of the model will have SIQ-JR as a function of time (discrete) and the interaction of condition by time (Twisk et al., 2018). Following the estimation of the mixed model, predictive marginal means will be computed and graphed in a margins plot to visualize the impact of condition on outcome over time. All analyses will be repeated for the secondary outcomes, adjusted where necessary to take into account characteristics (e.g. binary distribution) of these outcome measures. The stratification variable (previous suicide attempts) will be examined as covariates in the analyses. Nonparametric Wilcoxon rank sum tests will be used to compare number of sessions attended. We will examine the effect of the level of family conflict on the effect of ABFT in an exploratory analysis (interaction/confounding effect). CEA and CUA: General considerations Both the Cost-Effectiveness Analysis (CEA) and the Cost-Utility Analysis (CUA) will be conducted in agreement with the latest Dutch guideline on economic evaluations (Zorginstituut Nederland, 2024) and the Belgian guideline for economic evaluations (Cleemput et al., 2012), hence from the societal and health care payer perspectives and in agreement with the ITT principle. Two base-case analyses will be presented, one according to each country-specific guideline. Sensitivity analyses will be directed at uncertainty in the main cost drivers and outcomes. The CEA and CUA are conducted alongside the randomized trial which has follow-up measurements post-intervention and at three, six, and 12 months after intervention. CEA and CUA: Cost calculations Four types of costs will be included: (1) intervention costs (i.e. ABFT sessions), (2) costs stemming from health care utilization, (3) patients’ and their family’s costs for travel and informal care, (4) costs stemming from productivity losses due to absenteeism and lesser efficiency while at work (i.e. presenteeism), both in paid work and volunteer jobs. For the Belgium perspective, we will only include health care costs paid out of the health care budget, by the federal government, the communities and the patients, in line with the Belgian guideline. Data on resource use (health care uptake, informal care, travel distances to health services, and productivity losses) will be collected with the TiC-P (Timman et al., 2015). The TiC-P is the most widely used health service utilization interview for economic evaluations in the Netherlands, and can also be used in Belgium. Total costs will be estimated using a bottom-up (or micro-costing) approach, where units of health service are multiplied by their appropriate unit cost price and summed to provide an overall total cost estimate (Drummond et al., 2015). For the Dutch perspective, we shall make use of the standard unit cost prices as reported in the latest Dutch guideline for health economic evaluation (Hakkaart-van Roijen et al., 2015; Zorginstituut Nederland, 2024). For the Belgian perspective, unit prices will be taken from sources referred to in the Belgian guidelines for economic evaluations (e.g., Rijksinstituut voor ziekte- en invaliditeitsverzekering; NomenSoft). Costs of medication (and dispensing costs) will be calculated using prices based on Daily Defined Dosage (DDD) taken from www.farmacotherapeutischkompas.nl, www.medicijnkosten.nl or https://www.riziv.fgov.be/ , while accounting for the pharmacist’s claw back. Productivity losses will be based on the friction cost method as per the Dutch guideline and not included in the Belgium perspective. All costs will be expressed in 2022 euros. If necessary, existing cost prices will be updated to 2024 using the relevant national consumer price indices. CEA and CUA: Outcomes For the CEA, the central clinical end-term will be a dichotomized version of the SIQ-JR, in which patients who score ≥31 will be categorized to be at potentially serious risk for suicide. For the CUA, the Dutch and Belgium tariffs (utility weights) of the EQ-5D-5L will be used for computing QALYs (cf. www.euroqol.org). Utility values can be calculated for these health states, using preferences elicited from the Dutch and Belgian population (Bouckaert et al., 2021; Versteegh et al., 2016). CEA and CUA: Analysis The comparability of groups at baseline will be assessed for both costs and outcomes. When necessary, methods will be applied to control for baseline differences (Manca et al., 2005; Van Asselt et al., 2009). Missing cost and outcome data will be imputed using single imputation based on predictive mean matching nested in non-parametric bootstraps (Brand et al., 2019) for the ITT analysis. Since the trial’s follow-up measurements will exceed one-year, discounting will be performed in line with the Dutch and Belgian guidelines. Cumulative costs and health gains over the study’s follow-up period will be computed with the area under the curve method to obtain the remission rate and cumulative QALY health gains as accrued over the measurements up to last follow-up at 12 months. The incremental cost-effectiveness ratio (ICER) will be computed to obtain the incremental costs per reduced case of potentially serious risk for suicide and the incremental costs per QALY gained. Stochastic uncertainty will be handled using 5,000 non-parametric bootstraps and by plotting the simulated ICERs on the ICER-plane. For decision-making purposes, the cost-effectiveness acceptability curve will be plotted for various willingness-to-pay (WTP) ceilings for making judgements on whether adding ABFT offers good value for money relative to TAU. One-way sensitivity analyses directed at uncertainty in the main cost drivers and outcomes will be performed to assess the robustness of our findings (e.g. under different imputation strategies). Both the analysis and reporting of the research findings will conform to the (extended) CONSORT and CHEERS statements (Campbell et al., 2004; Husereau et al., 2013; Schulz et al., 2010). Monitoring Data monitoring: All study procedures will be monitored by a monitor from the Clinical Monitoring Center (CMC) of Ziekenhuis Oost-Limburg (ZOL). The monitor is independent from the sponsor, the funder, and the participating study sites. The monitor will perform on-site or remote visits following a monitoring plan agreed upon with the sponsor, before the start of the inclusion period, during the inclusion period and when all follow-up measurements at a specific site have taken place. The monitor will review details pertaining to data management, data administration, informed consent documents, inclusion and exclusion criteria, study procedures, and safety reporting. As there are no known harms associated with either the intervention or the control treatment, no other formal Data Safety Monitoring Board has been appointed and no planned interim analyses will be performed. A stopping rule cannot be stated, but at any stage the safety board of the sponsor may request reconsideration of the trial. In case the study is ended prematurely, the investigator will notify the accredited Medical Research Ethics Committee (MREC), including the reasons for the premature termination. There are no pre-defined criteria for ending the study. Safety monitoring: All adverse events (AE) reported spontaneously by the participants or observed by the investigator or site staff will be recorded. AEs are defined as any undesirable experience occurring to a subject during the study, whether or not considered related to the experimental intervention. We will also monitor and register Serious Adverse Events (SAEs), especially fatal suicides, suicide attempts, and any medical occurrences (accidents, other causes of death, hospitalizations) that can mask suicide attempts. This will be monitored by the treating therapists and research coordinator at the study site, who will inform the sponsor when an SAE occurs. All SAEs will be reported to the accredited MREC that approved the protocol. Ethics and dissemination Research ethics approval: The study protocol, information brochure, questionnaires and informed consent form are approved as a multicenter study by the Medical Research Ethics Committee of the Amsterdam UMC for the Dutch patients and the Ethics Committee Research UZ / KU Leuven for the Belgian patients. A model of the consent form for participants as well as the information brochure can be found in the Supplementary Material. Any modification as a result of a protocol amendment approved by the MREC will be communicated to the local principal investigators of the study site who will inform their respective teams. If a modification affects participants already in the trial, they will be informed about the change and ask to give informed consent for remaining the trial. Confidentiality and data access: All study and medical data will be coded and handled confidentially in accordance with the EU General Data Protection Regulation and the Dutch Act on Implementation of the General Data Protection Regulations. Participant data will be coded with a unique participant number and stored in Castor. A subject identification code list linking these participant numbers to the participant identification data will be created. This code list will only be available to the principal investigator of the study, staff members authorized by the principal investigator, the study monitoring agency and the Health and Youth Care Inspectorate. Statistical experts involved in the study who will analyze the (cost-)effectiveness of the intervention will only receive the coded data. Original source documents will be archived for a period of 15 years after the study report has been finalized and will be thereafter destroyed. A Data Protection Impact Assessment (DPIA) has been performed. An informed consent procedure has been set up that describes the data set, time span of data retention, information on sharing data or making data available for future research. Ancillary and post trial care: This is not applicable, as participants in the study can always benefit from ancillary care through their regular health care provider and health insurance. Although there are no expected risks for the participants, the sponsor has a liability insurance in case of any harm arising to participants from participation in the study. Dissemination policy: The results of the study will be shared with the participating mental health centers and in the relevant professional and scientific associations. The results will be presented on seminars and published in peer-reviewed journals. The results will not contain personal information. Pseudonymized data will be shared with multi-center sites upon reasonable request and after discussion on the intentions for which the data will be used. Discussion ABFT has been disseminated in mental health care settings in various Western countries, to treat adolescents with suicidal ideation, and has been increasingly used in emerging adults too (Diamond et al, 2022 ; DeVacht & Carlier, 2023; Van der Spek et al, 2023). ABFT is a family therapy intervention, targeting the attachment relationship with the caregivers, so that they can become a source of support and comfort in times of high distress, and help break the isolation of the suicidal young adult. Targeting attachment in suicidal youth is important. Because developing autonomy is a primary development task for emerging adults, and because they function increasingly independently of their parents, focusing therapy on repairing attachment bonds might seem an irrelevant and even an inappropriate intervention strategy in this age group. However, research points to the opposite. Autonomy development requires a secure attachment foundation (e.g., Gandi et al., 2016). When trust is ruptured, youth fail to seek support which jeopardizes their ability to freely explore their environment, as this puts them at risk to be exposed to distress, they cannot manage. This impairs their autonomy development (Bosmans, 2016). Emerging adults with severe mental health problems are often impaired in their attachment development, which makes it harder for them to develop autonomy and other competencies in this developmental phase (Devacht et al., 2019). These emerging adults struggle with their inability to develop the competencies that are considered normally acquired at this age. Moreover, due to the ruptures in their attachment bonds, they are not able to seek support for these struggles, eventually increasing their suicide risk. However, despite some promising results of several RCTs, and the positive outcomes of pilot and feasibility studies on ABFT showing high satisfaction and symptom decrease, the evidence for the effectiveness of ABFT as a treatment for suicidal ideation remains inconclusive (Schulte-Frankenfeld et al, submitted). Further systematic research into the (cost-)effectiveness of ABFT for emerging adults is needed for at least three reasons. First, the previous studies are all efficacy studies, conducted in a research setting. Therefore, a pragmatic RCT is needed that examines the effectiveness of ABFT in a setting in which this care is actually delivered in daily practice. This level of evidence is also crucial and needed for decision-making regarding clinical guidelines for suicidality and depression. Second, ABFT was developed for adolescents in the North American culture and might not fully be transferable to emerging adults in the Netherlands and Belgium. Our pilot studies indicated the acceptability and feasibility of ABFT in the Netherlands and Belgium (Van der Spek et al., 2023; Santens et al., 2019, DeVacht et al., 2019), and also for the young adult population. Nevertheless, an RCT is necessary to evaluate whether we indeed can yield similar effects in our culture. Third, worldwide the cost-effectiveness of ABFT, and to our knowledge any kind of family therapy, for suicidal patients has not yet been examined. This is important for dissemination policies. In addition, secondary analyses on mediators and predictors of effects can provide important knowledge on what types of treatments for suicidality work for whom. 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Supplementary Files SPIRITchecklistREPAIRStudy.docx SupplementaryFilesdesignpaper.docx Cite Share Download PDF Status: Published Journal Publication published 16 Oct, 2024 Read the published version in Trials → Version 1 posted Editorial decision: Major revision 23 Jul, 2024 Reviewers agreed at journal 27 Jun, 2024 Reviewers invited by journal 27 Jun, 2024 Editor assigned by journal 26 Jun, 2024 First submitted to journal 04 Jun, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Locatie AMC: Amsterdam UMC Locatie AMC","correspondingAuthor":false,"prefix":"","firstName":"Nadia","middleName":"van der","lastName":"Spek","suffix":""}],"badges":[],"createdAt":"2024-06-02 21:34:08","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-4518344/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-4518344/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1186/s13063-024-08499-7","type":"published","date":"2024-10-16T15:57:50+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":60711382,"identity":"556bcc3f-bc44-4fd8-9c0f-00fee44196be","added_by":"auto","created_at":"2024-07-19 20:18:18","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":51607,"visible":true,"origin":"","legend":"\u003cp\u003eFlow chart of study procedure\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-4518344/v1/5b7b0c2f861bb442ab6a4794.png"},{"id":67149539,"identity":"e0e30d83-2abb-44e9-8a72-12b8c7094597","added_by":"auto","created_at":"2024-10-21 16:13:07","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":458701,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-4518344/v1/c0fc66e0-771d-4865-a49f-38c67f0f022a.pdf"},{"id":60711383,"identity":"dc0b95b9-431c-4c99-8eee-6ed003de126c","added_by":"auto","created_at":"2024-07-19 20:18:19","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":41673,"visible":true,"origin":"","legend":"","description":"","filename":"SPIRITchecklistREPAIRStudy.docx","url":"https://assets-eu.researchsquare.com/files/rs-4518344/v1/9974f4ff02b182bd7f515d53.docx"},{"id":60711384,"identity":"01215b9a-4ee7-4869-b8e6-aaf1e74d4d83","added_by":"auto","created_at":"2024-07-19 20:18:19","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":147980,"visible":true,"origin":"","legend":"","description":"","filename":"SupplementaryFilesdesignpaper.docx","url":"https://assets-eu.researchsquare.com/files/rs-4518344/v1/d0fb447a1a5c71d1e7b6baa7.docx"}],"financialInterests":"","formattedTitle":"The Effectiveness and Cost-Effectiveness of Attachment Based Family Therapy for Young Adults with High Suicidal Ideation: Protocol of a Randomized Controlled Trial.","fulltext":[{"header":"Administrative information","content":"\u003cp\u003eThis study protocol follows the SPIRIT reporting guidelines (Chan et al., 2013). The SPIRIT Checklist can be found in the Supplementary Materials and offers an overview of where specific information can be found within the article.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTrial Status and Protocol version:\u003c/p\u003e\n\u003cp\u003eFirst approved protocol version in the Netherlands: Version 3, date May 8, 2023\u003c/p\u003e\n\u003cp\u003eLatest approved protocol version in the Netherlands: Version 8, date February 2, 2024\u003c/p\u003e\n\u003cp\u003eStart of recruitment: October 5, 2023\u003c/p\u003e\n\u003cp\u003eCurrent status: Recruitment ongoing\u003c/p\u003e\n\u003cp\u003eApproximate date of recruitment completion: May 2025\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRoles and responsibilities \u0026ndash; Contributorship:\u0026nbsp;Claudi Bockting, Guy Bosmans, and Nadia van der Spek designed the RCT, and drafted the initial research protocol.\u0026nbsp;Ben Wijnen and Joran Lokkerbol designed and wrote the statistical analysis and cost-evaluation section, with considerable input from\u0026nbsp;Micka\u0026euml;l Hiligsmann\u003csup\u003e\u0026nbsp;\u003c/sup\u003eand Geert Molenberghs. Derek de Beurs contributed to the initial design of the RCT and to the research protocol. Nele Bergers, and Luana Gavan helped revising the original research protocol and contributed to writing the final version of the manuscript, together with Nadia van der Spek and Claudi Bockting. Nadia van der Spek, Nele Bergers, Luana Gavan, Claudi Bockting are Guy Bosmans are currently coordinating the study. All authors gave feedback on the final manuscript version and approve the final version. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRoles and responsibilities \u0026ndash; Sponsor and funder: This work was funded by ZonMw and the Belgian Health Care Knowledge Centre (KCE), as part of the BeNeFIT (Belgium-Netherlands Funding of International Trials) programme.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRoles and responsibilities \u0026ndash; Committees: Several stakeholders participate in the Trial Steering Committee together with the research team and the funder Benefit. These are patient organisations Stichting Zelfbeschadiging, Depressievereniging, Ups \u0026amp; Downs, suicide prevention organisations 113online and VLESP.\u003c/p\u003e"},{"header":"Introduction","content":"\u003cp\u003eEmerging adult suicide is a serious problem around the world. Suicide is estimated to be the first to the fourth cause of death in the 15-29 years age group (WHO, 2021; CBS, 2020). Moreover, for each fatal suicide, approximately 20 non-fatal suicide attempts have been registered (WHO, 2014). Identifying and treating ultra-high suicide risk youth is one of the pressing current challenges in societies across the world (U.S. preventive service task force, 2022). The emotional cost for families and loved ones cannot be measured, but is clearly devastating. In addition, the economic and societal cost of fatal suicide is very high, and includes medical costs for individuals and families, lost income for families, and lost productivity for victims and family members (Shepard et al., 2015; Doran \u0026amp; Kinchin, 2020). Suicidal ideation is very prevalent among people with mental health disorders, such as depression (De Beurs et al, 2019). Suicidal ideation can result in suicide attempts and fatal suicide, but is in itself also very burdensome for individuals (Jaffe et al., 2019; Klaufus et al., 2022). The societal and economic burden of patients with suicidal ideation is higher compared to depressed patients without suicidal ideation (Benson et al., 2021). Therefore, suicidal ideation needs to be targeted with treatment. However, research on the treatment of youth suicidality lags significantly behind. Current treatments, including pharmacological treatment of suicidal emerging adults, have limited effects (Tondo \u0026amp; Baldessarini, 2016; Franklin et al, 2017). Treatment programs that can successfully treat emerging adults at high suicide risk are greatly needed and the societal impact of providing cost-effective treatment could be significant. \u003c/p\u003e\n\u003cp\u003eThus, tackling psychological mechanisms in treatment that contribute to decreasing young adult suicidality and depression is a critical next step to tackle suicidality. Until recently, standard treatment of suicidality consisted of cognitive behavioural therapy (CBT), dialectical behavioural therapy (DBT), and/or medication, but all showed limited effects on suicidality (Glenn et al., 2015; Fox et al., 2020; Franklin et al., 2017). Even worse, a recent meta-analysis of 50 years of treatment research found that the effect of existing treatments only produces small effects on suicidal behaviour (Franklin et al., 2017). A recent review (Asarnow \u0026amp; Mehlum, 2019) shows that there is only a limited number of evidence-based treatment options for adolescents that all only have limited treatment effects on suicidality, calling for more trials specifically targeting suicidality. Mixed support for the current treatments has contributed to the general recommendation to provide psychological treatments aimed at improving family relationships (Merelle et al., 2020; WHO, 2018). \u003c/p\u003e\n\u003cp\u003eFamily therapy is a less explored treatment option for suicidality. There is increasing evidence that points at the importance of working with families and addressing the unmet need for belonging and perceived burdensomeness when targeting youth suicidality (Asarnow \u0026amp; Mehlum, 2019; Merelle et al., 2020; Joiner et al., 2002, 2005, 2009). Even for emerging adults, who are in a developmental phase of striving for autonomy, not addressing family conflict might exacerbate the problem or inhibit the family from being a source of support for the patient (Devacht et al., 2019). In most cases, these emerging adults will either be living at home or be dependent on their families. The WHO recommends to involve the family in the treatment of suicidal youth as a powerful way to treat suicidality (WHO, 2018). One program that has been developed to specifically target suicidal youth, and that specifically focuses on the family, is Attachment Based Family Therapy (ABFT; Diamond et al., 2010, 2016, 2019).\u003c/p\u003e\n\u003cp\u003eABFT is a promising intervention for adolescents, gaining popularity around the world, that involves both the youngster and the caregivers. ABFT uses family therapeutic techniques to restore attachment relationships between members as a strategy to decrease youngsters\u0026rsquo; levels of depression and suicide risk (Diamond et al., 2016). Multiple studies have shown high acceptability and feasibility of ABFT for both adolescents and emerging adults (DeVacht et al., 2019; Diamond et al., 2022; Van der Spek et al., 2023; Santens et al., 2018; Santens et al., 2020). However, effectiveness studies have shown mixed results on suicidal ideation (Diamond et al., 2002, 2010, 2019; Waraan et al., 2021). Moreover, a recent meta-analysis on the RCTs up until now has shown no effect of ABFT on suicidal ideation among adolescents (Schulte-Frankenfeld et al., submitted). ABFT has never been studied in an RCT among emerging adults, who are in a developmental phase characterized by a different type of parent-child relationship. Therefore, more research is needed to establish whether ABFT is a cost-effective treatment for suicidal ideation and to investigate its effectiveness for emerging adults, instead of adolescents. \u003c/p\u003e\n\u003cp\u003eThe current RCT will compare ABFT added to treatment as usual (ABFT + TAU) to TAU alone among emerging adults between 18 and 25 years old, with high levels of suicidal ideation, receiving care in mental health care facilities in the Netherlands and Belgium. The main goal of the study is to assess the effectiveness and cost-effectiveness of ABFT added to TAU, compared to TAU alone, on suicidality in emerging adults over the course of five time points (baseline, post-treatment, three, six, and twelve months follow-up). Secondly, the effects of ABFT on depression, self-injury, entrapment, autonomy, family functioning, and young adult attachment will be investigated. \u003c/p\u003e"},{"header":"Methods/Design ","content":"\u003cp\u003eDesign\u003c/p\u003e\n\u003cp\u003eThis study is a randomized controlled pragmatic multi-center trial comparing Attachment Based Family Therapy (ABFT) added on to Treatment As Usual (TAU). Participants are suicidal emerging adults between 18 and 25 years old, who seek treatment, and their parents or caregivers.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe study will take place in 12 mental health care centers in the Netherlands and Belgium where suicidal patients are treated, including both inpatient and outpatient clinics, academic and non-academic treatment centers, and private practices. A list of all participating study sites can be found in the Supplementary Material. After regular intake procedures in the treatment facility, patients with suicidal ideation and their caregiver(s) will be informed about the study and asked to participate by a local researcher. After at least one week, the participants who are willing to participate, sign informed consent and will be screened on in/exclusion criteria by a researcher trained in the study protocol. Eligible patients and their parents/caregivers will be included in the study. After completing the baseline assessments, they will be randomized to ABFT+TAU or TAU alone. Follow-up interview assessments will take place post-intervention, at three, and at 12 months, by a researcher blinded to the treatment condition. Questionnaire assessments are administered at baseline, post-intervention, and at three, six (brief assessment for young adult only), and 12 months after intervention. Suicide attempts are registered during the interview assessments, and in the questionnaires for the youngster. As long as the participant is in treatment at the site, suicide attempts will be reported by the therapist. For more detailed information, see \u003cem\u003eFigure 1.\u003c/em\u003e \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eStudy sample\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eInclusion criteria are: a) between 18 and 25 years old, b) a score above the cut-off of the Suicidal Ideation Questionnaire Junior (SIQ-JR) (\u0026ge;31) and c) at least one parent or primary caregiver that participates in the assessments and treatment. This could be a biological parent, stepparent, grandparent, other relative, or a foster parent. Exclusion criteria are: a) Other DSM-5 disorders: severe alcohol or cannabis use disorder, for all other substances: moderate or severe substance use disorder, conduct disorder, evidence of psychotic features or prior psychosis; b) severe cognitive impairment (e.g., mental retardation, severe developmental disorders) as evidenced by educational records, parental report and/or clinical impression; c) other circumstances that might affect participation (e.g., severe medical disorder, relocation). \u0026nbsp;\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSample size calculation:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA recent meta-analysis, including three RCTs on ABFT for suicidal patients, found a Cohen\u0026rsquo;s d of 0.4 (Schulte-Frankenfeld et al., submitted). Based on this estimated effect size (Cohen\u0026rsquo;s d = 0.4), focused on the primary outcome (suicidality) and the proposed statistical analyses (i.e. Linear Mixed Modelling with five complete assessment time points), a base correlation across the 5 measurement of .5, an interclass correlation of patients \u0026apos;nested\u0026apos; in clinicians of .05, and assuming a design effect of 1.24 (given the clustered design), we will be needing \u0026asymp;46 participants per arm for a power of 80% and a nominal type I error of 0.05 to be able to show a medium effect of ABFT. Based on previous trials (Diamond, 2010, 2019), we estimate a 35% drop-out rate. We will therefore need a sample size of 71 ((46)/(1-0.35)) respondents per arm, resulting in a total of 142 participants.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRecruitment strategies:\u003c/p\u003e\n\u003cp\u003eParticipants will be recruited from the participating study sites by approaching them after intake or by searching for potential candidates in the existing caseload of therapists. Staff at the participating study sites have been informed about the study and can refer patients to the local study coordinator. The study will also be promoted via other channels such as personal network, news outlets, contact with suicide prevention organizations and general practitioners, as well as presence at relevant congresses and conferences, as a way to increase awareness about the study and reach the target sample size.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRandomization and stratification\u003c/p\u003e\n\u003cp\u003eEligible patients that gave informed consent, who are included in the study, will be randomized after baseline, through block randomization. A computer-generated randomization table with random block sizes will be prepared by an independent researcher not involved in the study. We will stratify on one variable: the number of previous suicide attempts (0 or \u0026gt;0). Stratification will be done per country, in order to maintain balanced treatment conditions across both countries. The result of the randomization procedure will be sent to the main study coordinator, who will then communicate it to the local principal investigator at the study site. The local principal investigator, who has been trained in the study protocol, is responsible for assigning participants to the correct therapist on the basis of the randomization outcome.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eBlinding and unblinding\u003c/p\u003e\n\u003cp\u003eOnly the researcher performing the follow-up interview assessments will be blinded to the treatment condition. Should unblinding occur inadvertently, then a different researcher will be assigned to perform follow-up assessments for that specific participant. Cases of unblinding during the interview assessment (e.g., the participant mentions their treatment condition to the interviewer) will be documented in a protocol deviation log.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eIntervention:\u003c/p\u003e\n\u003cp\u003eAttachment Based Family Therapy (ABFT) (Diamond et al., 2014) is a manualized treatment including 16 sessions, that emerges from interpersonal theories that suggest suicide can be precipitated, exacerbated, or buffered against by the quality of family relationships. ABFT is delivered by licensed clinical psychologists, psychotherapists, or psychiatrists who received nine days of training and 20 hours of supervision in ABFT. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAlthough ABFT therapists implement behavior-focused and psychoeducational interventions, the model is primarily a process-oriented, emotion-focused treatment, guided by a semi-structured treatment protocol. Suicide risk is monitored in every session by the therapist. Treatment is organized around five specific tasks, each with a distinct process and goal.\u0026nbsp;Each task refers to a specific treatment goal and offers a principle-driven guideline to achieve each goal. Task 1 (relational reframing) focuses on shifting the family\u0026apos;s treatment goal from \u0026ldquo;fixing the young adult\u0026rdquo; to improving family relationships. The Task 1 session\u0026nbsp;includes a discussion of what prohibits the youngster from turning to his or her parent(s)/caregiver(s) for help when feeling so hopeless and distressed, that they contemplate suicide. Family barriers range from: stress due to the youngster\u0026rsquo;s symptoms, history of negative interactions and communication, abuse, neglect, abandonment and/or parental psychopathology. Even well-functioning families need help effectively managing youth\u0026rsquo;s suicidality. Task 2 (alliance building with the youngster, three to four sessions) aims to help the youngster gain a better understanding of how ruptures in trust with the parents contribute to conflict and emotional distance. Emerging adults are then motivated and prepared to discuss these ruptures with their parents. Task 3 (alliance with the parents, three to four sessions) aims to help the parents become more empathic and sensitive to the youngster\u0026rsquo;s emotional needs. Task 4 (the attachment task, three to four sessions) brings all the family members back together to discuss some of the issues and ruptures that were identified in Tasks 2 and 3. ABFT considers caregiver support in response to the youngster\u0026apos;s shared experiences as a corrective attachment experience that helps repair trust. Task 5 (promoting autonomy) assumes that task 4 has built up enough trust that the parents can once again serve as a secure base to support the young adult\u0026rsquo;s competency and autonomy development. These five tasks provide a scaffold to guide the treatment. For this trial, we made a few adjustments to the treatment manual. First, at the beginning of the treatment, a family-oriented safety plan will be made for all patients receiving ABFT and will be used at all times during treatment when the patient is at high risk. Second, the developmental task of emerging adults, which involves obtaining autonomy and launching into adulthood, is central in the treatment. For instance, the Task 1 session is not mandatory if the young adult prefers to start with separate sessions. Task 4 is still about discussing ruptures, but also focuses on self-expression and individuating from the parents. No other treatment modifications will be performed. The possibility of discontinuing the allocated intervention will be discussed within each study site and with the participants\u0026rsquo; main therapist, taking into account participants\u0026rsquo; wishes and any safety-related concerns.\u003c/p\u003e\n\u003cp\u003eTherapists will receive supervision over their cases in the study.\u0026nbsp;All ABFT sessions will be videotaped and a randomly selected 15% of the tapes will scored by an independent rater to score treatment fidelity.\u0026nbsp;Treatment fidelity will be assessed with the\u003cem\u003e\u0026nbsp;Therapist Behavior Rating Scale-3\u003c/em\u003e (TBRS-3; Diamond, Hogue, Diamond \u0026amp; Siqueland, 1996). The TBRS-3 items demonstrated reliability with ICCs ranging from good (.69) to excellent (.96).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eTreatment as usual (TAU)\u003c/p\u003e\n\u003cp\u003eParticipants in both arms will receive TAU, in the experimental condition ABFT will be delivered as an add on. Most treatment centers\u0026rsquo; clinical practices rely heavily on the use of antidepressants and/or cognitive behavioral therapy (CBT) or dialectical behavior therapy (DBT). All regular interventions are allowed in TAU, except for systemic family therapy of more than 4 sessions in the first five months of the study (i.e. a family therapy session is defined as a contact of 30 minutes or longer with a family member or caregiver present). Parental involvement is generally part of treatment as usual, and can comprise for instance psycho-education, parental support, or skill training. We will monitor what TAU entails. TAU is not a comparator in this trial, as the trial aims to investigate whether ABFT is (cost-) effective as an add on to TAU, and not whether it is more effective than TAU.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eEligibility screening:\u003c/p\u003e\n\u003cp\u003eAfter signing informed consent, the eligibility will be assessed in a pretreatment session, using the SIQ-JR, the SCID-5-S interview, and patient records.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSuicidal Ideation Questionnaire Junior\u003c/em\u003e (SIQ-JR, Reynolds \u0026amp; Mazza, 1999), assesses suicidal ideation in youth in the past month. The SIQ-JR is a 15-item questionnaire, and has been used in many clinical studies. It forms a continuum ranging from thoughts of death and wanting to be dead, general and specific suicidal plans, preparations for/and actual suicide attempts. Eligible participants need to score above the cut-off of 31, which indicates potentially serious risk for suicide. The measure was found to be internally consistent (a = .94) with a test-retest reliability of .89 over three weeks. Participants indicate the frequency of certain ideations and behaviors in the past month, and respond to items like \u0026ldquo;I have thought about killing myself\u0026rdquo; on a 7-point Likert scale (0 not in the past month, till 6 almost every day in the past month). An extra item was added to assess suicide attempts (\u0026ldquo;I have tried to kill myself in the past week\u0026rdquo; (yes/no)). In case of a (fatal) suicide attempt, the highest SIQ-score will be given at that timepoint. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eThe exclusion criteria\u003c/em\u003e will be assessed using the \u003cem\u003eSCID-5-S interview\u003c/em\u003e. The SCID-5-S is designed as a semi-structured diagnostic interview for making the major DSM-5 diagnosis. Validation and reliability studies have been done on the SCID-S versions DSM-V, DSM-IV and DSM-III-R (Osorio et al, 2019; Lobbestael et al., 2011; Zanarini et al., 2000; Martin et al., 2000; Ramirez Basco et al., 2000; Fenning et al., 1994b, 1996; Zanarini \u0026amp; Frankenburg, 2001; William et al., 1992; and Skre et al., 1991). The results of these studies show that the validity and reliability of the SCID-S was good. The SCID-5-S can be administered effectively (mean 18.7 \u0026plusmn; 11.6 minutes, median 15 minutes). Clinicians can use it after a brief training session.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eBaseline only\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSocio-demographic factors and participant characteristics\u003c/em\u003e and \u003cem\u003eChildhood trauma\u0026nbsp;\u003c/em\u003eusing the\u003cem\u003e\u0026nbsp;Childhood Trauma Questionnaire\u003c/em\u003e (CTQ; Garnefski \u0026amp; Kraaij, 2001). This is a self-report 28-item questionnaire that measures 5 types of maltreatment: emotional, physical, and sexual abuse, and emotional and physical neglect (Garnefski \u0026amp; Kraaij, 2001). We include this questionnaire at baseline only, since childhood trauma is an important predictor of suicidality and depression. This questionnaire is not time-specific.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eOutcomes\u003c/p\u003e\n\u003cp\u003e\u003cem\u003ePrimary outcome\u003c/em\u003e: Change in suicidal ideation and behaviour as assessed by the Suicidal Ideation Questionnaire Junior (SIQ-JR; Reynolds \u0026amp; Mazza, 1999, see description above) in the young adult from baseline to post-intervention, three-, six- and twelve-months follow-up. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSecondary outcomes:\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eSuicide attempts and suicidality\u003c/em\u003e will be additionally investigated\u003cem\u003e\u0026nbsp;\u003c/em\u003eusing the\u003cem\u003e\u0026nbsp;Structured Clinical Interview DSM 5\u003c/em\u003e (SCID-5-S; Michael B. First, JBWW, Lorna Smith Benjamin, Robert L. Spitzer, 2017).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eEntrapment\u0026nbsp;\u003c/em\u003ewill be assessed using the\u003cem\u003e\u0026nbsp;Entrapment Short-Form Scale\u003c/em\u003e (E-SF; De Beurs et al., 2020). The E-SF is a 4-item questionnaire, which will be administered for the young adult only.\u003c/p\u003e\n\u003cp\u003eRespondents are asked to respond to statements on internal and external entrapment on a 5-point scale. Correlations between the sum of these four items and the 16-item full Entrapment Scale (Gilbert \u0026amp; Allan, 1998) were nearly perfect (0.94 for the clinical sample and 0.97 for the population-based sample).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eNon-Suicidal Self-Injury\u003c/em\u003e (NSSI; Buelens et al.2020).\u0026nbsp;This is a self-report 5-item questionnaire that measures non-suicidal self-injury\u0026nbsp;and will be administered for the young adult only.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eDepressive symptomatology\u0026nbsp;\u003c/em\u003eas assessed by\u003cem\u003e\u0026nbsp;Patient Health Questionnaire\u003c/em\u003e (PHQ-9; Kroenke, Spitzer \u0026amp; Williams, 2001)\u003cem\u003e.\u003c/em\u003e The PHQ-9 is recommended in the core outcome set for depression and represents the outcomes that matter most to patients with depression. It is a 9-item questionnaire, demonstrating good reliability and responsiveness to change, with Cronbach\u0026rsquo;s alphas ranging from 0.82 to 0.92 (Cameron et al., 2008),\u0026nbsp;and will be administered to the young adult only.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eWorld Health Organization Disability Assessment 2.0\u0026nbsp;\u003c/em\u003e(WHODAS 2.0;\u0026nbsp;\u0026Uuml;st\u0026uuml;n et al., 2010), is part of the core outcome set for depression, consisting of 12 items covering the domains of Cognition, Mobility, Self-care, Getting along, Life activities and Participation. The WHODAS is a questionnaire with good validity and reliability (\u0026Uuml;st\u0026uuml;n et al., 2010), and will be administered to the young adult only.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eThe Self Report Measures of Family Functioning\u003c/em\u003e (SRFF; Stark et al., 1990) is composed of 15 five-item factors measuring family functioning (e.g., cohesion, conflict, and democratic family style) with Cronbach\u0026apos;s alphas ranging from .63 to .91, with most in the .70 to .85 range. Analyses have yielded highly reliable and stable factors (Stark et al., 1990). We will administer the SRFF to the young adult as well as the parents.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eYoung adult attachment:\u0026nbsp;\u003c/em\u003eTo measure secure attachment in the young adult, we will use the Secure Base Script Task (SBS;Waters \u0026amp; Waters, 2006). This is a narrative task during which participants need to construct stories (six items for six stories) with prompt words that loosely suggest a secure base script, due to participants who know the script cannot suppress telling secure base script stories. This measure correlates highly and significantly (\u003cem\u003er\u0026nbsp;\u003c/em\u003e= .50) with attachment interviews that are considered valid in the field of attachment research (Waters et al., 2019; Waters \u0026amp; Roisman, 2019).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eAutonomy of the young adult\u003c/em\u003e, as assessed by the questionnaire\u003cem\u003e\u0026nbsp;My Parents and I\u003c/em\u003e (Van Petegem, 2008), a combination of items of the Emotional Autonomy Scale (EAS; Steinberg \u0026amp; Silverberg, 1986) and the Psychological Separation Inventory (PSI; Hoffman, 1984),\u0026nbsp;will be administered for the young adult only.\u0026nbsp;The reliability of the combined scales, indicated by Cronbach\u0026apos;s alpha, amounts to .84.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eChildrens Depression Inventory second edition\u003c/em\u003e (CDI-2, Bodden et al., 2016)\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eThe CDI-2 for parents consists of 17 items, scored on a 4- point Likert scale to indicate how often in the past two weeks symptoms occurred in their child. They respond to statements like \u0026ldquo;Looks sad\u0026rdquo; (0=not at all, 1=sometimes, 2=often, 3=almost always). A CDI-2 cut-off score of 16 is indicative of \u0026ldquo;significant\u0026rdquo; depressive symptoms according to the Dutch Mental Health Care guideline (Buitelaar et al., 2009: Multidisciplinaire Richtlijn GGZ, Addendum Depressie bij Jeugd, 2009)\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eCost-effectiveness\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eHealth care and associated costs and costs from productivity loss (TiC-P;\u0026nbsp;\u003c/em\u003eHakkaart-Van Roijen, 2002). The TIC-P is a questionnaire assessing participants\u0026rsquo; healthcare resource use and productivity losses, including school and work drop out. The TIC-P will be administered at every measurement point and will inquire about healthcare resource use and productivity losses since the previous measurement (and in case of baseline for the three months prior to baseline). The TIC-P will be administered to the emerging adults only.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eHealth-related quality of life\u0026nbsp;\u003c/em\u003e(EQ-5D-5L; Bouckaert et al., 2021; Versteegh et al., 2016). The EuroQOL five dimensions (EQ-5D) is a short questionnaire used to assess utilities of the young adult at each measurement. Utilities are converted into Quality-Adjusted Life Years (QALYs), using Dutch and Belgian tariffs. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDuring-treatment assessment every two months\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eWorking Alliance Inventory\u003c/em\u003e (12-item WAI; Horvath \u0026amp; Greenberg, 1986). The WAI measures overall therapeutic alliance and consists of subscales measuring (quality of therapy) tasks, goals and bonds. This measure has strong psychometric properties and has been used widely in psychotherapy research (Tracey \u0026amp; Kokotovic, 1989).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eTherapy Procedure Checklist\u003c/em\u003e (TPC, Weersing et al., 2002). The TPC is developed to assess therapists\u0026apos; reports of the techniques they employ when working with child and adolescent clients, and will be used to monitor TAU in both study arms. TPC items encompass the three most common therapeutic models for youth: psychodynamic, cognitive, and behavioral. TPC scales have good internal consistency (all alpha \u0026gt; .86) and test-retest reliability (all r \u0026gt; .79) across samples. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003eData collection and data management:\u003c/p\u003e\n\u003cp\u003eData will be collected through questionnaires (using the clinical research platform Castor Electronic Data Capture) or (clinical) interviews. All data will be collected by researchers either from the study site or the sponsor, who have been trained in the study protocol, procedures and assessments. An electronic CRF (Castor) is used to collect a part of the data, a copy of the blank CRF pages is kept as back-up. Some data will be collected through a CRF on paper and will be entered in Castor afterwards. Access to the data collection system is based on individual login and access rights are only given to authorized staff. For each study-specific data collection, source documentation is available. Budget is allocated both for storage during the study as well as for archiving upon completion of the study. Budget is allocated for data management activities and creating a FAIR dataset.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eRetention:\u003c/p\u003e\n\u003cp\u003eParticipant retention will be promoted by sending regular reminders for completion of assessments both by researchers. Participants are also encouraged to complete all follow-up assessments by receiving a monetary incentive. Participants who decide to discontinue treatment can continue to participate in the study. If participants decide to discontinue study participation, they can continue treatment without any additional consequences. An early termination assessment will be done for participants who decide to discontinue participation.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eData processing and statistical analysis:\u003c/p\u003e\n\u003cp\u003eThe data will be stored in a generic and machine actionable format, i.e. SPSS, R or excel. The acquired data will be stored as read-only file and a new file will be created for further processing and statistical analysis. All data processing and analysis will be programmed in syntax or script files. Descriptive comments will be added to the syntax or script files. Data sets and syntax or script files will be placed under version control. Data corrections in this phase will be programmed in syntax or script files. With regard to sharing data for processing or statistical analysis, data will transfered in a secure way. Encoded data from participating sites will be collected using secured links or during a site visit.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eStatistical analyses:\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAll analyses will be performed blind by an independent researcher on the intention-to-treat sample. As per the CONSORT statement, baseline data will be presented by presenting mean and standard deviations for continuous variables (or median and a centile range when asymmetrically distributed) and by using numbers and proportions for categorical variables. Quantitative outcome measures will be analyzed using Linear Mixed Modelling, using all five assessment time points of the primary outcome measure. A similar (but Generalized) approach will be applied to estimate the impact on secondary outcomes.\u0026nbsp;Our data, which is expected to contain missing values due to dropout, can be analyzed under the relatively relaxed assumption of missingness at random using linear mixed modelling (Verbeke \u0026amp; Molenberghs, 2000; Molenberghs \u0026amp; Kenward, 2017). Mixed modelling will be used to evaluate the impact of condition (ABFT vs TAU) on SIQ-JR scores over all five measurements with participant ID as random effect. The fixed part of the model will have SIQ-JR as a function of time (discrete) and the interaction of condition by time (Twisk et al., 2018). Following the estimation of the mixed model, predictive marginal means will be computed and graphed in a margins plot to visualize the impact of condition on outcome over time. All analyses will be repeated for the secondary outcomes, adjusted where necessary to take into account characteristics (e.g. binary distribution) of these outcome measures.\u003c/p\u003e\n\u003cp\u003eThe stratification variable (previous suicide attempts) will be examined as covariates in the analyses. Nonparametric Wilcoxon rank sum tests will be used to compare number of sessions attended. We will examine the effect of the level of family conflict on the effect of ABFT in an exploratory analysis (interaction/confounding effect).\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCEA and CUA: General considerations\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eBoth the Cost-Effectiveness Analysis (CEA) and the Cost-Utility Analysis (CUA) will be conducted in agreement with the latest Dutch guideline on economic evaluations (Zorginstituut Nederland, 2024) and the Belgian guideline for economic evaluations (Cleemput et al., 2012), hence from the societal and health care payer perspectives and in agreement with the ITT principle. Two base-case analyses will be presented, one according to each country-specific guideline. Sensitivity analyses will be directed at uncertainty in the main cost drivers and outcomes. The CEA and CUA are conducted alongside the randomized trial which has follow-up measurements post-intervention and at three, six, and 12 months after intervention. \u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCEA and CUA: Cost calculations\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eFour types of costs will be included: (1) intervention costs (i.e. ABFT sessions), (2) costs stemming from health care utilization, (3) patients\u0026rsquo; and their family\u0026rsquo;s costs for travel and informal care, (4) costs stemming from productivity losses due to absenteeism and lesser efficiency while at work (i.e. presenteeism), both in paid work and volunteer jobs. For the Belgium perspective, we will only include health care costs paid out of the health care budget, by the federal government, the communities and the patients, in line with the Belgian guideline. Data on resource use (health care uptake, informal care, travel distances to health services, and productivity losses) will be collected with the TiC-P (Timman et al., 2015). The TiC-P is the most widely used health service utilization interview for economic evaluations in the Netherlands, and can also be used in Belgium. Total costs will be estimated using a bottom-up (or micro-costing) approach, where units of health service are multiplied by their appropriate unit cost price and summed to provide an overall total cost estimate (Drummond et al., 2015). For the Dutch perspective, we shall make use of the standard unit cost prices as reported in the latest Dutch guideline for health economic evaluation (Hakkaart-van Roijen et al., 2015; Zorginstituut Nederland, 2024). For the Belgian perspective, unit prices will be taken from sources referred to in the Belgian guidelines for economic evaluations (e.g., Rijksinstituut voor ziekte- en invaliditeitsverzekering; NomenSoft). Costs of medication (and dispensing costs) will be calculated using prices based on Daily Defined Dosage (DDD) taken from www.farmacotherapeutischkompas.nl, www.medicijnkosten.nl or \u003ca href=\"https://www.riziv.fgov.be/\"\u003ehttps://www.riziv.fgov.be/\u003c/a\u003e, while accounting for the pharmacist\u0026rsquo;s claw back. Productivity losses will be based on the friction cost method as per the Dutch guideline and not included in the Belgium perspective. All costs will be expressed in 2022 euros. If necessary, existing cost prices will be updated to 2024 using the relevant national consumer price indices.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCEA and CUA: Outcomes\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eFor the CEA, the central clinical end-term will be a dichotomized version of the SIQ-JR, in which patients who score \u0026ge;31 will be categorized to be at potentially serious risk for suicide. For the CUA, the Dutch and Belgium tariffs (utility weights) of the EQ-5D-5L will be used for computing QALYs (cf. www.euroqol.org). Utility values can be calculated for these health states, using preferences elicited from the Dutch and Belgian population (Bouckaert et al., 2021; Versteegh et al., 2016).\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cem\u003eCEA and CUA: Analysis\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThe comparability of groups at baseline will be assessed for both costs and outcomes. When necessary, methods will be applied to control for baseline differences\u0026nbsp;(Manca et al., 2005; Van Asselt et al., 2009). Missing cost and outcome data will be imputed using single imputation based on predictive mean matching nested in non-parametric bootstraps\u0026nbsp;(Brand et al., 2019)\u0026nbsp;for the ITT analysis. Since the trial\u0026rsquo;s follow-up measurements will exceed one-year, discounting will be performed in line with the Dutch and Belgian guidelines. Cumulative costs and health gains over the study\u0026rsquo;s follow-up period will be computed with the area under the curve method to obtain the remission rate and cumulative QALY health gains as accrued over the measurements up to last follow-up at 12 months. The incremental cost-effectiveness ratio (ICER) will be computed to obtain the incremental costs per reduced case of potentially serious risk for suicide and the incremental costs per QALY gained. Stochastic uncertainty will be handled using 5,000 non-parametric bootstraps and by plotting the simulated ICERs on the ICER-plane. For decision-making purposes, the cost-effectiveness acceptability curve will be plotted for various willingness-to-pay (WTP) ceilings for making judgements on whether adding ABFT offers good value for money relative to TAU. One-way sensitivity analyses directed at uncertainty in the main cost drivers and outcomes will be performed to assess the robustness of our findings (e.g. under different imputation strategies). Both the analysis and reporting of the research findings will conform to the (extended) CONSORT and CHEERS statements\u0026nbsp;(Campbell et al., 2004; Husereau et al., 2013; Schulz et al., 2010).\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMonitoring\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eData monitoring:\u003c/p\u003e\n\u003cp\u003eAll study procedures will be monitored by a monitor from the Clinical Monitoring Center (CMC) of Ziekenhuis Oost-Limburg (ZOL). The monitor is independent from the sponsor, the funder, and the participating study sites. The monitor will perform on-site or remote visits following a monitoring plan agreed upon with the sponsor, before the start of the inclusion period, during the inclusion period and when all follow-up measurements at a specific site have taken place. The monitor will review details pertaining to data management, data administration, informed consent documents, inclusion and exclusion criteria, study procedures, and safety reporting. As there are no known harms associated with either the intervention or the control treatment, no other formal Data Safety Monitoring Board has been appointed and no planned interim analyses will be performed. A stopping rule cannot be stated, but at any stage the safety board of the sponsor may request reconsideration of the trial. In case the study is ended prematurely, the investigator will notify the accredited Medical Research Ethics Committee (MREC), including the reasons for the premature termination. There are no pre-defined criteria for ending the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eSafety monitoring:\u003c/p\u003e\n\u003cp\u003eAll adverse events (AE) reported spontaneously by the participants or observed by the investigator or site staff will be recorded. AEs are defined as any undesirable experience occurring to a subject during the study, whether or not considered related to the experimental intervention. We will also monitor and register Serious Adverse Events (SAEs), especially fatal suicides, suicide attempts, and any medical occurrences (accidents, other causes of death, hospitalizations) that can mask suicide attempts. This will be monitored by the treating therapists and research coordinator at the study site, who will inform the sponsor when an SAE occurs. All SAEs will be reported to the accredited MREC that approved the protocol.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics and dissemination\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eResearch ethics approval:\u003c/p\u003e\n\u003cp\u003eThe study protocol, information brochure, questionnaires and informed consent form are approved as a multicenter study by the Medical Research Ethics Committee of the Amsterdam UMC for the Dutch patients and the Ethics Committee Research UZ / KU Leuven for the Belgian patients. A model of the consent form for participants as well as the information brochure can be found in the Supplementary Material. Any modification as a result of a protocol amendment approved by the MREC will be communicated to the local principal investigators of the study site who will inform their respective teams. If a modification affects participants already in the trial, they will be informed about the change and ask to give informed consent for remaining the trial.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eConfidentiality and data access:\u003c/p\u003e\n\u003cp\u003eAll study and medical data will be coded and handled confidentially in accordance with the EU General Data Protection Regulation and the Dutch Act on Implementation of the General Data Protection Regulations. Participant data will be coded with a unique participant number and stored in Castor. A subject identification code list linking these participant numbers to the participant identification data will be created. This code list will only be available to the principal investigator of the study, staff members authorized by the principal investigator, the study monitoring agency and the Health and Youth Care Inspectorate. Statistical experts involved in the study who will analyze the (cost-)effectiveness of the intervention will only receive the coded data. Original source documents will be archived for a period of 15 years after the study report has been finalized and will be thereafter destroyed. A Data Protection Impact Assessment (DPIA) has been performed. An informed consent procedure has been set up that describes the data set, time span of data retention, information on sharing data or making data available for future research.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eAncillary and post trial care:\u003c/p\u003e\n\u003cp\u003eThis is not applicable, as participants in the study can always benefit from ancillary care through their regular health care provider and health insurance. Although there are no expected risks for the participants, the sponsor has a liability insurance in case of any harm arising to participants from participation in the study.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eDissemination policy:\u003c/p\u003e\n\u003cp\u003eThe results of the study will be shared with the participating mental health centers and in the relevant professional and scientific associations. The results will be presented on seminars and published in peer-reviewed journals. The results will not contain personal information. Pseudonymized data will be shared with multi-center sites upon reasonable request and after discussion on the intentions for which the data will be used.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eABFT has been disseminated in mental health care settings in various Western countries, to treat adolescents with suicidal ideation, and has been increasingly used in emerging adults too (Diamond et al, \u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e2022\u003c/span\u003e; DeVacht \u0026amp; Carlier, 2023; Van der Spek et al, 2023). ABFT is a family therapy intervention, targeting the attachment relationship with the caregivers, so that they can become a source of support and comfort in times of high distress, and help break the isolation of the suicidal young adult.\u003c/p\u003e \u003cp\u003eTargeting attachment in suicidal youth is important. Because developing autonomy is a primary development task for emerging adults, and because they function increasingly independently of their parents, focusing therapy on repairing attachment bonds might seem an irrelevant and even an inappropriate intervention strategy in this age group. However, research points to the opposite. Autonomy development requires a secure attachment foundation (e.g., Gandi et al., 2016). When trust is ruptured, youth fail to seek support which jeopardizes their ability to freely explore their environment, as this puts them at risk to be exposed to distress, they cannot manage. This impairs their autonomy development (Bosmans, 2016). Emerging adults with severe mental health problems are often impaired in their attachment development, which makes it harder for them to develop autonomy and other competencies in this developmental phase (Devacht et al., 2019). These emerging adults struggle with their inability to develop the competencies that are considered normally acquired at this age. Moreover, due to the ruptures in their attachment bonds, they are not able to seek support for these struggles, eventually increasing their suicide risk.\u003c/p\u003e \u003cp\u003eHowever, despite some promising results of several RCTs, and the positive outcomes of pilot and feasibility studies on ABFT showing high satisfaction and symptom decrease, the evidence for the effectiveness of ABFT as a treatment for suicidal ideation remains inconclusive (Schulte-Frankenfeld et al, submitted). Further systematic research into the (cost-)effectiveness of ABFT for emerging adults is needed for at least three reasons. First, the previous studies are all efficacy studies, conducted in a research setting. Therefore, a pragmatic RCT is needed that examines the effectiveness of ABFT in a setting in which this care is actually delivered in daily practice. This level of evidence is also crucial and needed for decision-making regarding clinical guidelines for suicidality and depression. Second, ABFT was developed for adolescents in the North American culture and might not fully be transferable to emerging adults in the Netherlands and Belgium. Our pilot studies indicated the acceptability and feasibility of ABFT in the Netherlands and Belgium (Van der Spek et al., 2023; Santens et al., 2019, DeVacht et al., 2019), and also for the young adult population. Nevertheless, an RCT is necessary to evaluate whether we indeed can yield similar effects in our culture. Third, worldwide the cost-effectiveness of ABFT, and to our knowledge any kind of family therapy, for suicidal patients has not yet been examined. This is important for dissemination policies. In addition, secondary analyses on mediators and predictors of effects can provide important knowledge on what types of treatments for suicidality work for whom. Regarding the mixed results found in previous studies, this study is crucial to examine the effectiveness and cost-effectiveness of ABFT, a promising family therapy intervention for suicidal emerging adults.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e"},{"header":"Declarations","content":"\u003ch2\u003eFunding:\u003c/h2\u003e \u003cp\u003eThis study is funded by BeNeFit-ZonMw/KCE\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAsarnow, J. R., \u0026amp; Mehlum, L. (2019). Practitioner Review: Treatment for suicidal and self-harming adolescents \u0026ndash; advances in suicide prevention care. \u003cem\u003eJournal of Child Psychology and Psychiatry,\u003c/em\u003e\u003cem\u003e \u003c/em\u003e\u003cem\u003e60\u003c/em\u003e(10), 1046\u0026ndash;1054. https://doi.org/10.1111/jcpp.13130\u003c/li\u003e\n\u003cli\u003eBarker, E., Kolves, K., \u0026amp; De Leo, D. (2017). 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Retrieved February 13, 2024, from https://www.who.int/publications/i/item/9789240026643\u003c/li\u003e\n\u003cli\u003eZorginstituut Nederland. \u0026quot;Richtlijn voor het uitvoeren van economische evaluaties in de gezondheidszorg.\u0026quot; \u003cem\u003eDiemen: Zorginstituut Nederland\u003c/em\u003e (2024).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":true,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"trials","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"trls","sideBox":"Learn more about [Trials](http://trialsjournal.biomedcentral.com/)","snPcode":"13063","submissionUrl":"https://www.editorialmanager.com/trls","title":"Trials","twitterHandle":"MedicalEvidence","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-4518344/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-4518344/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eYoung adult suicidality is worldwide a prevalent mental health problem and the number one cause of death, with devastating consequences for individuals and their families, and substantial economic costs. However, psychological and pharmacological treatments currently recommended in guidelines for treatment of high-risk youth for fatal suicide have limited effect. In line with the WHO\u0026rsquo;s recommendation to involve the family in treatment of these youth, Attachment Based Family Therapy (ABFT) was developed; a 16-week attachment and emotion-focused treatment, implemented in mental health care settings across various European countries in the past years, and is becoming increasingly popular among therapists. However, the (cost-)effectiveness of ABFT has not been studied in emerging adults. In the proposed pragmatic RCT we aim to evaluate the effectiveness and cost-effectiveness of ABFT compared to Treatment As Usual (TAU) on suicidality, as delivered in daily practice. This pragmatic multicenter study in the Netherlands and Belgium includes 12 participating sites. Participants are suicidal young adults (\u0026ge;\u0026thinsp;31 SIQ-JR score) between 18 and 25 years old who seek mental health treatment (n\u0026thinsp;=\u0026thinsp;142) and their caregivers. The primary outcome is suicidality (SIQ-JR), with assessments at baseline, post-intervention (five months after baseline), three, six and twelve months after intervention. We predict that, compared to TAU, ABFT will lead to a stronger reduction in suicidality and will be more cost-effective, over the course of all timepoints. We also expect stronger decreases in depressive symptoms, given that suicidality is very common in individuals with depressive disorder, as well as more improvement in family functioning, autonomy, entrapment, and young adult attachment, in the ABFT condition. This study can contribute to improving the care for suicidal youngsters with high mortality risk. Treatment of suicidal emerging adults is understudied. The results will inform clinical guidelines and policy makers and improve treatment of suicidal emerging adults.\u003c/p\u003e","manuscriptTitle":"The Effectiveness and Cost-Effectiveness of Attachment Based Family Therapy for Young Adults with High Suicidal Ideation: Protocol of a Randomized Controlled Trial.","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-07-19 20:18:14","doi":"10.21203/rs.3.rs-4518344/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Major revision","date":"2024-07-23T12:36:31+00:00","index":"","fulltext":""},{"type":"reviewerAgreed","content":"","date":"2024-06-27T06:55:16+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-06-27T06:54:22+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-06-26T07:33:21+00:00","index":"","fulltext":""},{"type":"submitted","content":"Trials","date":"2024-06-04T14:11:27+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"trials","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"trls","sideBox":"Learn more about [Trials](http://trialsjournal.biomedcentral.com/)","snPcode":"13063","submissionUrl":"https://www.editorialmanager.com/trls","title":"Trials","twitterHandle":"MedicalEvidence","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"3e4b41c9-c22a-4ae4-9b22-f9653a99c5e4","owner":[],"postedDate":"July 19th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2024-10-21T16:08:31+00:00","versionOfRecord":{"articleIdentity":"rs-4518344","link":"https://doi.org/10.1186/s13063-024-08499-7","journal":{"identity":"trials","isVorOnly":false,"title":"Trials"},"publishedOn":"2024-10-16 15:57:50","publishedOnDateReadable":"October 16th, 2024"},"versionCreatedAt":"2024-07-19 20:18:14","video":"","vorDoi":"10.1186/s13063-024-08499-7","vorDoiUrl":"https://doi.org/10.1186/s13063-024-08499-7","workflowStages":[]},"version":"v1","identity":"rs-4518344","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-4518344","identity":"rs-4518344","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}