Testing an attachment- and trauma-informed intervention approach for parents and young children after interparental violence: protocol for a randomized controlled trial

In order to reduce the impact of interparental violence on young children, the parent-child relationship might be a key target for intervention [15, 16]. For victimized parents who have been abused by their (ex-)partner, parenting may become extremely challenging due to post-traumatic stress disorder (PTSD) symptoms and related psychopathology [10, 17]. Children who are exposed to interparental violence and related adversities have a high risk of developing psychopathology as well, including PTSD [18, 19]. A secure attachment relationship can protect children from developing maladaptive psychological outcomes [20‐22], also after experiences of child maltreatment [23, 24]. While children who have been exposed to interparental violence would therefore urgently need a stable and nurturing attachment relationship as a buffer to protect them from (further) developing trauma-related symptomatology, in reality, such caregiving is in short supply. Victimized parents who suffer from PTSD symptoms and related psychopathology are often unable to support their child and they are more likely to show frightened and frightening behaviors towards their child, which compromises treatment and healthy development of the child [25, 26]. An attachment-based parenting program would therefore be vital to promote secure attachment interactions between traumatized parents and their children, which would consequently result in a reduction of children’s PTSD symptoms and related psychopathology [27‐29]. See Fig. 1 for a conceptual overview.

To this moment, very few randomized controlled trials (RCTs) have been conducted specifically aimed at preschool children who have been exposed to interparental violence. One such study is a trial that investigated the effect of Child-Parent Psychotherapy (CPP) in a sample of mothers and children between the age of 3 and 5 years old who had witnessed interparental violence [16, 30]. CPP is an attachment-based intervention that is conducted through weekly sessions for the duration of 1 year. This intervention adopts a trauma-informed approach: the development of a joint trauma narrative of the parent and child is a central element throughout the intervention. The RCT showed that CPP led to a reduction of trauma-related symptomatology in both children and their mothers. Unfortunately, in this study, the quality of parent-child interactions was not assessed. This implies that we can only speculate that the effects on child and parental trauma symptoms occurred through an improved parent-child relationship, since this is a main focus of the intervention program. Nevertheless, this trial showed that CPP is a suitable intervention for traumatized mothers with young children. A disadvantage of this intervention is that it is quite lengthy (weekly sessions for the duration of 1 year). Besides the high costs and long duration of this intervention, CPP demands that certain conditions are met, such as a safe and stable family situation over a relatively long period of time, which limits the implementation of this program in practice. Several studies evaluating attachment-based interventions for parents (at risk for) child maltreatment have shown that short-term attachment-based interventions (duration shorter than 3 months) can also be effective in promoting the quality of parent-child interactions and children’s well-being [31‐33]—although such optimistic findings are not consistently reported [34, 35]. Advantages of short-term attachment-based interventions are that the costs are relatively low and that completing these interventions in this hard-to-reach population of families is less challenging. Another drawback of the CPP trial is that children younger than 3 years old were not included, even though CPP was designed for younger children as well. It has thus not yet been empirically investigated how the needs of traumatized infants and toddlers who have been exposed to interparental violence can be best addressed.

In the current study, we will advance the current knowledge on effective treatment of this population by evaluating the effectiveness of NIKA, a video-feedback intervention aimed at enhancing the attachment relationship, in a sample of victimized parents and their young children (0.5–6 years old) after severe interparental violence. This intervention was selected for this study in a preliminary study that was conducted prior to the trial [36]. This preliminary study involved a literature search and an expert meeting involving a group of therapists with ample experience in conducting trauma- and attachment-based interventions in the Netherlands. The main practical reasons to select NIKA for this study were that this intervention was developed specifically for families after interparental violence or other types of child maltreatment and that NIKA is already being used in several domestic violence shelters throughout the Netherlands, which will likely facilitate implementation of the current study’s results in Dutch practice.

Adults who are victims of interparental violence are at an increased risk for developing PTSD [37, 38]. This risk is further exacerbated by the fact that many victimized adults have a history of chronic and interpersonal traumatization themselves, for instance resulting from experiences of childhood maltreatment [39, 40]. In line with the concept of relational PTSD, it might be expected that if parents show reduced PTSD symptoms, for example after receiving trauma therapy, this would lead to improved parent-child interactions, more security for the child, and therefore a reduction of PTSD symptoms in the child as well. Following this line of reasoning, it would be important that parents who suffer from PTSD symptoms and related psychopathology receive trauma therapy to reduce their own PTSD symptoms—among which those symptoms that interfere with the parent-child relationship.

For individual treatment of adult PTSD, meta-analytic evidence consistently demonstrates the effectiveness of EMDR therapy and trauma-focused cognitive behavior therapy (TF-CBT) [41‐45], also for adults with PTSD resulting from childhood maltreatment [46]. Both interventions are therefore recommended in several Dutch and international guidelines [47‐49]. Nevertheless, several arguments favor the use of EMDR therapy relative to TF-CBT in the specific context of this study. First, a recent economic analysis showed that EMDR therapy is the most cost-effective trauma intervention for adults [50]. In addition, in the expert meeting that was organized for our preliminary study, the large majority of experts considered EMDR therapy as the most appropriate therapy for victimized parents who have experienced interparental violence, because this is an efficient therapy that leads to PTSD symptom reductions in a short time frame [36]. To our knowledge, the effectiveness of EMDR therapy (or any other trauma therapy) for the specific group of victimized parents after interparental violence has not yet been empirically investigated. In the current study, we aim to fill this gap by evaluating whether EMDR therapy can be used to reduce PTSD symptoms in this population.

Because of the complementary primary foci of NIKA and EMDR therapy, it would be valuable to explore the synergetic effects of these two interventions. While NIKA adopts a trauma-sensitive approach by explicitly linking parents’ past traumatic experiences to dysfunctions in their current parenting behavior, for parents who suffer from PTSD symptoms, their ongoing trauma symptomatology might still be an interfering factor in the relationship with their child. Individual trauma therapy focused on reducing their own PTSD symptoms might then be additionally needed in order to further improve the parent-child relationship. Hence, we hypothesize that if parents with clinical PTSD symptoms additionally receive EMDR therapy after NIKA, they would show an even greater decrease in disrupted parenting behavior and a greater increase in sensitive parenting behavior compared to parents with clinical PTSD symptoms who only receive NIKA. Considering the direct and indirect impact of parental PTSD symptoms and related psychopathology on the development of young children, this should also be reflected in a stronger decrease in PTSD symptoms and related psychopathology of the child. This assumption has not yet been empirically tested, but several studies did investigate whether parental traumatization hampers the effectiveness of attachment-based parenting interventions. Although one study did not confirm this hypothesis [51], three other studies did show that traumatized parents responded less well to these interventions [52‐54]. These latter findings support the assumption that individual trauma therapy focused on the parent, in addition to an attachment-based intervention such as NIKA, would generate increased effects.

To our knowledge, there is currently no specific evidence available concerning the most effective order in which to offer attachment-based treatment versus parent-focused trauma therapy (if there even is one specific order which would work best for all families). Therefore, we relied on clinical experience to determine the order of these two interventions in this study. We chose to start by offering NIKA, followed by EMDR, for several reasons. First, parents who receive treatment from a domestic violence shelter are often dismissive towards their own psychological distress (so-called survival mode) and therefore less open to receive treatment focused on reducing their own PTSD symptoms. They are usually more motivated to receive treatment that involves their child(ren), as is the case with an attachment-based intervention such as NIKA. Throughout the NIKA sessions, parents become increasingly aware of the impact of their own (potentially disrupted) behaviors on their child and the link between these behaviors and their own traumatic experiences. In addition, after NIKA the child’s behavior likely becomes easier to handle, which might leave the parent with more mental space to engage in a trauma therapy such as EMDR. Hence, we expected that, even though this order might not be the best order for every dyad, this order would be the most generic. In a separate study, we aim to generate more knowledge on determining the best order of attachment- and trauma-based treatment components for this population.

NIKA is a short-term video-feedback intervention aimed at enhancing the parent-child relationship for parents and their children aged between 0 and 6 years old [14]. The intervention specifically targets high-risk families, for instance, families where child maltreatment or other forms of domestic violence have occurred. The goal of NIKA is to prevent or reduce disorganized attachment and related psychopathology in children by reducing disrupted parenting behavior and increasing sensitive parenting. The intervention uses elements from cognitive behavior therapy and is based on attachment theory. Even though NIKA has similar elements to several existing attachment-based video-feedback interventions (e.g., Basic Trust [58] and Video-feedback Intervention to promote Positive Parenting and Sensitive Disciplining, VIPP-SD [59]), NIKA has a stronger emphasis on diminishing disrupted patterns in the attachment relationship. NIKA was developed by ND and KZ and is already in use in several domestic violence shelters in the Netherlands. The NIKA manual includes the theoretical background of the intervention and a clear protocol to support therapists during the intervention. It also includes several working materials for parents (e.g., a homework assignment) to help them transfer their newly acquired skills to their everyday life.

NIKA is provided through a structured protocol. NIKA starts with an assessment session consisting of an attachment interview, a questionnaire, and a video observation. For the video observation, the parent and child are asked to play together for a couple of minutes while a few mild stressors are added. In this trial, the video recordings that are made during the pre-test are used for this purpose (stressors in this session include the use of age-inappropriate toys, a too large variety of toys, and the instruction to clean up the toys after a couple of minutes). The goal of the assessment is to get acquainted with the child’s attachment behaviors, the disrupted patterns that are present in the parent-child relationship, and the roots of these patterns in the parent’s own trauma history, as well as the parent’s reflective functioning and sensitive behaviors. After the assessment session, several video-feedback sessions take place. For this trial, we standardized the number of video-feedback sessions so that each dyad will receive four video-feedback sessions of 1 h each. These sessions have a similar structure: first, the therapist helps the parent formulate a personalized goal and reflect on the parent’s interactions with the child. The therapist and parent then discuss the video recordings that were made during the previous session. The therapist uses psycho-education (supported with visual materials) to explain what sensitive parenting behavior is and helps the parent reflect on his or her parenting behavior based on the psycho-education and video recordings. Throughout the session, the therapist stimulates the parent to mentalize about the child’s behaviors, thoughts, and feelings in the video recordings (e.g., “What is your child thinking right now?”). In case the parent has dysfunctional cognitions about the child (e.g., if the child is playing on its own and the parent interprets this behavior as if the child is rejecting him or her), cognitive restructuring techniques are used to change these cognitions. The parent is reinforced by the therapist whenever the parent displays adequate insights or reflections. To provide the parent with feedback on disrupted parenting behavior, the therapist selects a fragment that reflects a disrupted pattern in the parent-child relationship. The video is first paused at a moment where the child shows attachment-eliciting cues. The parent is asked what the child would feel, think, and need in this instant. Subsequently, the disrupted parenting behavior that follows in the video recording is displayed to the parent. The therapist reflects on this moment with the parent by discussing the relation between this parenting behavior and the parent’s own traumatic history. The parent is explained what the negative effect of this behavior is on his or her child, by showing the child’s response in the video recording and providing the parent with psycho-education. The therapist also gives the parent specific advice on how to improve the disrupted parenting behavior. At the end of the feedback session, the therapist shows a fragment in which the parent displays sensitive parenting behavior. This way, the parent is reinforced in his or her abilities as a parent and feels more confident. In the final session, the assessments of the intake session are repeated and the therapist and parent reflect on the effect of the feedback sessions.

Only parents who report clinical PTSD symptoms assessed with the PTSD Checklist for the DSM-5 (PCL-5, score ≥31 [60]) during post-test 1 (see Fig. 2) are randomized to one of the trauma therapy conditions (EMDR versus waitlist usual care). For a more detailed explanation of this instrument and the cut-off score that was used, see the “Outcomes {12}” section. EMDR therapy is a protocolized, eight-phase trauma therapy, which aims to reduce symptoms resulting from disturbing and unprocessed traumatic experiences. This method includes history taking, preparation, assessment, desensitization, installation, body scan, positive closure, and reevaluation [61]. Before the onset of the EMDR sessions, a case conceptualization is made with the parent (1 session of max 90 min) to identify the traumatic events that are currently related to their PTSD symptoms and have the most negative impact on the parent-child relationship. These may be traumatic experiences during and before parenthood, for example during childhood. Memories will be placed in a hierarchy based on the Subjective Units of Disturbance (SUD) and are treated subsequently from high to low SUD. During treatment, patients are asked to memorize the most distressing part of the experienced traumatic event, including images, thoughts, emotions, and physical sensations. At the same time, their working memory capacities are challenged by visually tracking the horizontally moving finger of the therapist (or a light bar) or other stimuli to maximize the workload of the working memory, such as hand-held buzzers. For a full description of the treatment protocol, see Shapiro [61]. In the current trial, the Dutch version of the standard EMDR protocol is used [62] and a maximum of 5 weekly sessions of EMDR therapy will be applied with a duration of 90 min each. It is assumed that some of the participants are able to process multiple memories per session. Therefore, early completers are expected in this study. Treatment completion is defined as receiving five sessions, or less if (a) SUD scores are zero for all identified traumatic memories and (b) there is an agreement between the parent and therapist that the PTSD symptoms are sufficiently reduced to warrant terminating treatment.

We conducted a power analysis for longitudinal linear mixed effect models with unbalanced designs in R using the “powerlmm” package [76]. Based on recent meta-analyses regarding the effectiveness of trauma-informed parenting interventions after violence exposure [77] and a short-term attachment-based intervention that includes some components similar to NIKA [78], we assumed an effect size of d = 0.50 for the effects of NIKA on disrupted and sensitive parenting. We estimated three-level models accounting for repeated measures over time (level 1) and partial nesting of families (level 2) within therapists (level 3) (only in the NIKA group). We estimated approximately 50% variance to occur between subjects and 5% variance between therapists. For a sample of N = 150 (n = 75 per group), two time points, and two-sided testing with a significance level of α = .05, we will have 86% power to detect effects of d = 0.50.

The estimated effect size of EMDR therapy on PTSD symptoms of the mother is based on a recent meta-analysis in which effect sizes of EMDR therapy were reported within a range of g = 0.67–1.18 [79]. Because the current implementation of EMDR therapy (focus on memories of traumatic events that are related to their PTSD symptoms and also hinder positive parent-child interactions) is different from previous studies, we decided to stay on the conservative side of this range by assuming an effect size of d = 0.60 for this study. We estimated three-level models accounting for repeated measures over time (level 1) and nesting of mothers (level 2) within the previous condition (NIKA versus waitlist) (level 3). We estimated approximately 50% variance to occur between subjects and 5% variance between previous conditions (NIKA versus waitlist). For a sample of N = 80, (n = 40 per group), two time points, and two-sided testing with a significance level of α = .05, we will have 75% power to detect effects of d = 0.60. With a sample of N = 150 in phase 1, this would imply that 53% of the mothers who are recruited for this study should report clinical trauma symptoms in order to be included in the randomization for phase 2. We made this estimation based on a recent report which revealed that all women in one of the participating domestic violence shelter locations experienced severe and chronic domestic violence and 75% of the women report traumas of their own childhood [80].