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The Role of a Research Assistant (Part 1)

As a research assistant working with the National Centre for Mental Health (NCMH), I am pleased to talk about an exciting collaboration between NCMH and the Traumatic Stress Research Group (TSRG) at Cardiff University.

In part one of this blog, I will talk about our current understanding of traumatic stress and the recent global shift in the recognition of the different ways in which it can present.

In part two, I will discuss the questions that this recognition has created, which NCMH and the TSRG are committed to exploring.

Part One:

A new era in our understanding of traumatic stress

What is traumatic stress?

It is a difficult reality that many of us will experience trauma at some point in our lives. Traumatic events are events which are extremely horrifying in nature and involve actual or threatened death, serious injury or sexual violation. Whether this be a single event like a car accident or assault, or a series of events such as those experienced during a tour of duty or through domestic violence. Such events might happen directly to us, we might witness them happening to others, or we might learn about them happening to someone close to us.

In the aftermath of trauma, it is not uncommon to experience a degree of psychological distress. With time, for most this distress will subside. However, for some, the psychological wounds of trauma may continue to be as fresh in the months, years or even decades that follow. For these individuals, it is possible that they may be suffering symptoms of Post-Traumatic Stress Disorder, or PTSD.

Although there is disagreement between diagnostic classification systems about the exact definition of PTSD, the symptoms agreed as common to different definitions of the disorder are shown below. These include intrusive re-experiencing of a traumatic experience in the here-and-now, accompanied by avoidance of reminders and an ongoing sense of threat.

How are disorders of traumatic stress diagnosed?

In order to provide a label, or diagnosis, for a set of symptoms, clinicians refer to one of two classification systems; (i) the 11th revision of the International Classification of Diseases (ICD11), published by the World Health Organization in 2018, or (ii) the 5th revision of the Diagnostic Statistical Manual of Mental Disorders (DSM-5), published by the American Psychiatric Association in 2013.

There exists much heated debate about psychiatric diagnosis as a construct. However, despite this, there is no denying the place it has in today’s society. Whatever your opinion on psychiatric diagnosis, as is the case for disorders of physical health, a diagnosis for many provides an understanding of their suffering and enables signposting to evidence-based interventions.

One reason for the differences between DSM-5 and ICD-11 is that the latter is intended to provide a ‘common vocabulary’ (WHO, 2018) for diagnosis on a global scale. This makes it possible to map world-wide trends in health statistics and impacts decisions about how to programme health services, allocate health care spending, and invest in research and development (WHO, 2018). In order for these aims to be achieved, diagnostic criteria should be easily understood and applicable to cultures across the globe. The availability of clear, concise criteria with a high degree of validity is therefore crucial.

There however remain many barriers to appropriate psychiatric diagnosis. Ironically, one of the major barriers may well be the diagnostic criteria themselves, which arguably, historically, have not provided useful definitions of disorders of traumatic stress. For almost as long as PTSD has been formally recognised as a diagnosis, survivors, researchers and clinicians have, therefore, tirelessly been making the case for more informed and thus clinically useful definitions of traumatic stress reactions.

In 2018, revisions to the ICD11 diagnostic criteria for disorders of traumatic stress aimed to reflect these efforts. The revisions included refined diagnostic criteria for Post-Traumatic Stress Disorder (PTSD) and recognition of a new, sibling disorder of Complex PTSD (CPTSD).


The revised ICD11 criteria for PTSD have been narrowed to include only six symptoms spread over three symptom clusters; re-experiencing, avoidance and hyperarousal. Together, these symptoms are believed to conceptualise PTSD as a fear-based disorder. This is in contrast to the DSM-5 criteria, which include 20 symptoms spread over four symptoms clusters which arguably deviates from a fear-based conceptualisation of PTSD.

The DSM-5 criteria therefore encompass a much broader range of symptoms which may arise following traumatic events. Although the DSM-5 criteria are extremely comprehensive, this is possibly at the expense of specificity for traumatic stress symptoms. This may exacerbate confusion for clinicians when distinguishing PTSD from other disorders which may share similar symptoms. The simplified ICD11 criteria, arguably with a higher specificity for traumatic stress symptoms, may help reduce this confusion and enable clinicians to feel more confident in arriving at an appropriate diagnosis.

The ICD11 criteria also recognise that, although common, not all of those with PTSD will experience symptoms indicating negative alterations in cognitions and mood. ICD11 therefore does not require the presence of such symptoms for a diagnosis of PTSD to be made. The recognition of CPTSD as a distinct disorder however reflects an understanding that some survivors of traumatic events develop a more pervasive pattern of problems which share similarities with some of these symptoms.

ICD11 Complex PTSD

According to the ICD11 conceptualisation, CPTSD encompasses all of the symptoms of PTSD as well as symptoms reflecting what is referred to as a ‘disturbance in self organisation’ which arise or worsen following trauma. These symptoms concern a person’s thoughts about themselves, their ability to manage their emotions and their relationships with others.

The term CPTSD was first coined in 1992 by the Psychiatrist Judith Herman in her book Trauma and Recovery (Herman, 1992). The concept of CPTSD has been revised and refined since this time and, although not formally recognised as a diagnosis until 2018, the term has been widely used to describe such presentations which reflect a more pervasive pattern of problems that often don’t respond as well to typical treatments for PTSD.

Prior to 2018, numerous attempts were made at categorising these symptoms into psychiatric diagnoses, many of which have since been abandoned. In the absence of a useful conceptualisation of these symptoms, there has likely been great confusion over how best to approach treatment. For individuals presenting to services with such symptoms, it is possible that this confusion has exacerbated their suffering, leading them to receive inappropriate diagnoses and treatments.

ICD11’s recognition of CPTSD as a sibling diagnosis, as well as the clear and concise criteria by which it is defined, is therefore incredibly encouraging. For a diagnosis of CPTSD to be made, criteria for PTSD must be fulfilled in addition to one of two symptoms from each of the ‘disturbance in self organisation’ clusters.

The future of PTSD research

The ICD11 revisions to the criteria for PTSD and the recognition of CPTSD as a separate diagnosis have been embraced by many survivors, clinicians and researchers in the traumatic stress field. Indeed, these revisions are arguably long overdue, since it has been recognised for a number of decades that many people present with symptoms which have not been accurately reflected in the diagnostic criteria available. However, due to the disparity the ICD11 revisions have created with the DSM-5 criteria, for the time being a degree of confusion over the diagnosis of disorders of traumatic stress will continue to persist.

The National Centre for Mental Health and Traumatic Stress Research Group at Cardiff University hope to address this confusion by exploring some of the pressing research questions which the ICD11 revisions have created. The goal of this cannot be understated: to ultimately reduce the suffering of those who experience trauma through better understanding, diagnosis and treatment of traumatic stress.

In part two of this blog, I will talk about some of the specific questions that these revisions have created and what researchers at Cardiff University are doing to pave the way in exploring these.


American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). Washington, DC: Publisher.

Herman, J. (1992). Trauma and recovery. New York: Basic Books

World Health Organization. (2018, June 18). Coding disease and death. Retrieved from

World Health Organization. (2018). International classification of diseases for mortality and morbidity statistics (11th revision). Retrieved from