Is mental health staff training in de-escalation techniques effective in reducing violent incidents in forensic psychiatric settings? – A systematic review of the literature

In mental health services violence is a current and relevant problem for professionals as well as patients [1]. A meta-analysis of 35 international studies including 23,972 inpatients showed that the proportion of patients who committed at least one act of interpersonal violence was 17% [2]. In a recent German study, including 64,367 admissions in psychiatric hospitals, 17,599 aggressive incidents were recorded throughout the year 2019 [3]. This study described that 5084 (7.90%) of the admitted patients showed aggressive behavior towards others. Amongst the 1,660 forensic inpatients included in this study, the proportion of aggressive behavior was even higher (20.54%). At least in Germany, data also suggest an increase of violent incidents in psychiatric hospitals over the last ten years [3].

British authors found that on forensic psychiatric wards there are higher rates of violence compared to general psychiatry [4, 5]. Referring to German psychiatric hospitals, forensic psychiatry had the highest proportion of cases with aggressive behavior (20.54%), but the number of incidents per bed was lower than in general adult psychiatry as well as in child and adolescent psychiatry [3]. Violent behaviour includes verbal and physical threats and aggression that may lead to serious injury or death. The risk of these behaviours is significant in forensic settings. This is due to the complex historical and current psychosocial needs of the patient group [6]. Among other things, the resulting damage includes physical and psychological injuries to fellow patients and staff, diminished therapeutic relationships, lower job-satisfaction of the employees as well as an increase in the number of days of sick leave [7‐10].

Although they are untherapeutic, restrictive interventions (i.e. manual restraint, mechanical restraint, seclusion or forced medication) are used in psychiatric hospitals as well as in forensic mental health services in order to manage aggressive behaviour. However, this kind of coercion should exclusively be used if de-escalation and other preventive strategies have failed and there is potential for harm to patients or employees if no action is taken [11]. The use of restrictive interventions is very problematic for patients, staff and organizations [12]. They diminish the therapeutic alliance between staff and patients. Patients experience restrictive interventions as dehumanizing, frightening, confusing and at times painful [13, 14]. Restrictive interventions are associated with anxiety and stress and can cause physical and psychological damage for both patients and staff [15, 16]. Both staff and patients might suffer injury [17]. Moreover, especially mechanical restraint or isolation can be highly traumatic. Occasionally, restrictive measures can not only result in serious physical harm, but even patient deaths (e.g. due to physical restraint) [18, 19].

The recommended first-line response to potential violence and aggression in healthcare settings is de-escalation [11, 20, 21]. This means that, especially in forensic psychiatric settings, staff need to intervene before situations escalate to a level when there seems to be no other choice but using restrictive interventions to protect themselves as well as the health and lives of their other entrusted patients. Referring to Bowers et al., until 2011 there seemed to be no systematic description of the concept of de-escalation in the healthcare context [22]. Nowadays, terms like “de-escalation”, “de-escalation techniques” or “de-escalation training” seem to be defined rather vaguely, as well. Nevertheless, it isn’t possible to reasonably define the content of de-escalation trainings without clarifying these terms [22]. For the purpose of this review it is therefore necessary to make a serious attempt to establish a working definition of de-escalation techniques.

In 2012 Price and Baker strived to clarify what the term “de-escalation techniques” means in current literature [23]. Accordingly, de-escalation techniques are “a set of therapeutic interventions frequently used to prevent violence and aggression within mental health services” [23]. They describe that de-escalation techniques consist of several “key components”. In a thematic literature synthesis Price and Baker found seven themes describing these key components. These themes were related either to staff skills (characteristics of effective de-escalators; maintain personal control; verbal and non-verbal-skills) or the process of intervening (engaging with the patient; when to intervene; ensuring safe conditions for de-escalation and strategies for de-escalation). In 2014, based on the aforementioned description of de-escalation techniques, Price et al. conducted a systematic review about the learning and performance outcome of mental health staff training in de-escalation techniques for the management of violence and aggression [24]. In this review they describe that de-escalation techniques aim to stop the escalation of aggression to either violence or the use of physically restrictive practices via a range of psychosocial techniques. These psychosocial techniques would “typically involve the use of non-provocative verbal and non-verbal clinician communication to negotiate a mutually agreeable solution to the aggressor’s concerns” [23, 24]. Referring to Price and Baker [23] Bower developed a simplified and rather linear model portraying “de-escalation as a process, starting with delimiting the situation, then moving on to clarification of the problem with the patient concerned, followed by reaching a resolution” [4]. According to Bower this process “is only likely to succeed if, at every stage, the de-escalator is controlling their own emotions and expressing respect and empathy for the patient they are seeking to de-escalate “. In 2017, Hallett et al. conducted a concept analysis of de-escalation of aggressive behaviour in healthcare settings [20]. They found that, considering the available literature, de-escalation in healthcare settings could be characterized as “a collective term for a range of interwoven staff delivered components comprising verbal and non-verbal communication, self-regulation, assessment, actions, and safety maintenance, which aims to extinguish or reduce or reduce patient aggression/agitation irrespective of its cause, and improve staff-patient relationships while eliminating or minimising coercion or restriction.” They also describe that de-escalation “comprises a set of skills, knowledge, and personal features in the domains of communication, self-regulation, assessment, activity, and safety maintenance “. Evidently, there is a great overlap in the aforementioned definitions regarding their key elements in terms of content. However, Hallet et al. as well as Baker use the term “de-escalation”, while Price and Baker refer to “de-escalation techniques”.

The current review focuses on the effectiveness of mental health staff training in de-escalation techniques in forensic psychiatric settings. The working definition of “de-escalation techniques” underlying this manuscript corresponds essentially to the aforementioned concept as suggested by Price et al. [23, 24]. Accordingly, de-escalation techniques are regarded as a set of interwoven, (partially) learnable, non-physical, psychosocial techniques with the aim of stopping an impending escalation of inpatient aggression to violence in mental health services. On the one hand, the key components of these de-escalation techniques include themes relating broadly to staff skills. These staff skills include verbal skills (e.g. negotiating, tactful language, using a calm tone of voice, sensitive use of humour), non verbal-skills (e.g. attentive posture and body language, active listening, a certain degree of eye contact), the ability to maintain personal control when faced with inpatient aggression as well as the ability to express a positive, emphatetic, supportive and non authoritarian therapeutic attitude. On the other hand, de-escalation techniques accordingly include themes relating broadly to the process of intervening. This implies the ability to engage with the patient and to make reasonable assessments (e.g. about the necessity and timing of intervening; about what level of staff support is necessary and whether the area is safe). Furthermore, de-escalation strategies are regarded as key components of de-escalation techniques (e.g. shared problem solving, facilitating expression, offering alternatives to aggression, limit-setting).

Training in de-escalation techniques is often a key feature of complex interventions for reducing restraint and seclusion [23]. For years, staff training including de-escalation components to prevent and reduce verbal and physical aggression has been adopted in mental health settings. These training programs intend to promote prevention, relational security and the de-escalation of conflicts. Several different training programmes are already in use.

A concrete example of such a training program is “ProDeMa” (Professional Deescalation Management) [25, 26]. ProDeMa is program that, referring to its authors, is explicitely focused on training a mental health staff on de-escalation techniques. The program was developed in Germany and intends to reduce violent incidents through 7 “de-escalation levels”:

All in all, in the field of general psychiatry the available data concerning key outcomes (e.g. assault rate, incidence of aggression, use of physical restraint) are rather mixed. Literature reviews about the effectiveness of de-escalation training respectively training in de-escalation techniques in reducing the use of coercive measures propose that more evidence is needed to evaluate their effectiveness [24, 27]. However, some weak indications for the efficacy of mental health staff training in de-escalation techniques in reducing violent incidents as well as the use of restraint and seclusion have already been found within the field of general psychiatry [24, 27, 28]. For example, a few studies found a significantly reduced risk of physical assaults on ward level [24, 29‐31] respectively a significant reduction of aggressive incidents including verbal aggression and violence towards objects [24, 29, 31].

We conducted a systematic literature search of publications from 2002 (the year ProDeMa was developed) up until December 2021.The search included the electronic data bases Cochrane Library, Ovid PsycInfo, PubMed, Science direct, Scopus and Web of Science. We combined search terms capturing forensic settings with various terms relating to health care professionals as well as deescalation. The full search strategy is included in the Supplementary Material.

Our selection included studies related to the evaluation/assessment of a staff training program to reduce violent incidents in forensic psychiatric hospitals. Particular emphasis was placed on mental health staff training referring to de-escalation techniques regarding the research question "Is mental health staff training in de-escalation techniques effective in reducing violent incidents in forensic psychiatric settings?".

The initial searches returned 15398 potentially relevant titles. Results of the searches were reviewed independently by authors PG and DB for suitability for inclusion in the review against the criteria set out below. This was initially undertaken through inspection of titles and abstracts. A second review appraising the full papers was then undertaken as required. In the event of a difference of opinion over a paper’s suitability for inclusion a third author (BV) was consulted. Additionally, authors DB and PG searched reference lists from both included and excluded studies for further suitable papers for inclusion. Using this approach, one more suitable study was found. A total of 174 papers were shortlisted because they seemed to describe studies in a forensic psychiatric hospital having deescalation training as a topic or being about describing the type, severity, frequency or reduction of violent incidents. After screening the abstracts 145 of these papers were excluded because they didn’t fit our selection criteria. Thirty full texts were finally screened. 5 papers fulfilled our selection criteria and were consequently included in this review. A flow chart of our search results is set out in Fig. 1. Details of the studies are shown in Table 1.

The number of studies examining the effects of staff training in de-escalation techniques in forenic psychiatric settings was very limited. Five studies were finally deemed relevant for this review. The considered studies took place in hospitals in Israel (2), Norway (1), UK (1) and Australia (1). None of the studies was a RCT. One study was designed as a one-group-posttest-only. 4 studies were designed as before-and-after-comparisons-without-control-group. The number of participants per rating ranged from 8 to 112. The training periods lasted from 0,5 days to 3 weeks.

Nesset and colleagues conducted a pilot study in a Norwegian forensic psychiatric hospital consisting of 16 beds in order to investigate whether a nursing staff training program improves the ward atmosphere and patient satisfaction [40]. The 3 weeks staff training taught issues around de-escalation techniques using lectures as well as role plays. Week one focused on principles of milieu therapy, week 2 on how the nature of work in forensic psychiatry affects the nursing staff emotionally and how the staff could contain aggressive feelings from the patients. In week 3 setting limits was practiced, e. g. in role plays. After the intervention, nursing staff received no further teaching but weekly supervision continued and themes from the staff training program became a common element in these supervisions. The perception of the treatment atmosphere was measured by the revised Ward Atmosphere Scale (WAS-R) at three time points: before, immediately after and six months after the intervention [42]. The WAS-R is a self-report questionnaire including 11 subscales of which one measures the perception of angry and aggressive behavior displayed by the patients. Patients and staff reported a significantly lower level in the WAS-subscale “angry and aggressive behavior” after the intervention. The authors concluded that it might be possible to effectively improve the ward atmosphere through conducting a nursing staff training program [40]. However, besides the small sample size and the absence of a control group an important limitation of this study is that it didn’t evaluate explicitely whether the frequency (as opposed to the subjective assessment of patients and staff) of violent incidents actually reduced.

Martin and Daffern conducted a one-group-post-test-only study evaluating clinician perceptions of personal safety and confidence to manage inpatient aggression in a forensic psychiatric setting [41] following a staff training programme with a de-escalation techniques component, called M4 (“Managing the team, Managing the environment, Managing the patient and Managing aggression”). M4 consists of a 2-day workshop including theoretical (“organizational incidence and patterns of aggression, risk assessment, legal framework, therapeutic culture, crisis communication and deescalation skills, pharmacology, therapeutic interventions, critical incident stress management”) and practical elements (“self-defense and constraint”). All newly-appointed clinicians had to attend the workshop. After that, they were obliged to attend at least three refresher sessions (1,5 h each) per year. The main measured outcome results of the study were clinician perceptions of personal safety and confidence to manage inpatient aggression. These parameters were measured using a self-report questionnaire based on Thackrey’s “Confidence in Coping with Patient Aggression Instrument” [41, 43]. Clinicians reported the hospital as safe and found themselves relatively confident concerning their ability to manage aggressive patient behavior. Besides this, staff training on aggression management was reported as the most supportive factor on confidence in managing aggression. Whether the clinicians confidence in management inpatient aggression as well as the percepted personal safety translate into an actual reduction in incidents can, however, not be concluded reliably from this study. Neither is it possible to determine whether this positive assessment was objectively related to the training programme. Other limitations of the study were the small sample size, the absence of a control group as well as employing a questionnaire that was not validated.

Davies and colleagues investigated the effectiveness of multiprofessional staff training (79 trainees) in “positive behavioral support” (PBS) in increasing staff confidence and changing attributions of challenging inpatient behavior in a medium secure forensic mental health service in Wales, UK [44]. The training package around PBS included identifying primary and secondary (violence) prevention strategies. Methodologically the study was designed as a before and after comparison without control group. PBS includes de-escalation techniques such as verbal-deescalation and prevention of challenging behaviors. It can be described as a non-aversive approach to preventing and managing challenging behavior (e. g. aggressive/violent behavior of patients) through increasing the confidence of staff in their own abilities dealing with aggressive patients. Training for qualified staff took one day. It covered theoretical content as well as the practice of associated skills such as identifying primary and secondary prevention strategies of challenging behavior. Training for unqualified staff was limited to half-a-day and covered primarily theoretical aspects. To evaluate the effectiveness of the staff training program Davies et al. used self-report questionnaires. To measure the staff’s confidence an adapted version of Thackrey’s “Confidence in Coping with Patient Aggression Instrument” [43] was used. The staff's attributions of challenging inpatient behavior were measured using the “Challenging Behavior Attribution Scale” and the “Causal Dimension Scale “. After the intervention the confidence in working with challenging inpatient behavior increased significantly for both qualified and unqualified staff. Particularly for qualified staff, attribution of challenging behavior to external causes increased as well. It could be hypothesized that the staff’s confidence and attribution changes might have de-escalating effects and thus a violence reducing effect on the wards. However, an important limitation of the study is the fact that it didn’t focus on this concrete aspect. There is no evaluation whether the effects extend to objective data, such as numbers of actual incidents. Furthermore, there was no control group.

Isaak and colleagues examined the effectiveness of a 3-day intervention program (“Return home safely”) in a before and after comparison without control group in a high-secure forensic psychiatric (total of 132 beds) setting in Israel [38]. The training program was designed to enhance unit safety climate, to reduce patient violence and employee risk of injury from patient violence. The program contains several elements referring to the definition of de-escalation techniques as mentioned in the text above [23, 24]. Day one focusses on personal safety (i.e. how to avoid dangerous situations, self-defense skills, methods for safely restraining patients). Day 2 is mainly about tools for successful inter-staff communication. One day 3 staff issues around organizational learning are addressed (i.e. how to conduct incident investigations after adverse events). The outcome measures consisted of a questionnaire, recording of violent incidents and staff injuries. The 21-item safety climate questionnaire [45] distributed to hospital staff immediately before the workshop and again after 6 months contained 3 safety climate measures, i.e. communication about safety issues, procedures and safety reporting and perceived management commitment to safety. Following the training there was a significant improvement in perceived management commitment to safety as well as a marginally significant improvement in communication about safety issues as well as in procedures and safety reporting. The number of violent incidents and staff injuries also decreased significantly. Before the intervention program about 31 aggressive incidents toward staff were reported annually on average during the period from 2004 to 2007. After the intervention program about 15 aggressive incidents toward staff were reported annually on average during the period from 2008 to 2013. An important limitation of the study is its design, especially the absence of a control group.

The same group evaluated the (long-term) effectiveness of annual refresher training sessions of the training program at reducing critical incidents (e.g. physical aggression towards staff) [39]. The authors found that the rate of incidents in the years 2009 to 2017 was kept low in comparison to the pre-intervention years. About 12 aggressive incidents toward staff were reported annually on average during the period from 2009 to 2017. Again, important limitations of the study primarily are the small sample size and the absence of a control group.