Post Traumatic Stress Disorder (PTSD) – Diagnosis and History Taking | CASC Article and Video

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To remember the core features of PTSD, think of TRAVEL: Trauma, Re-experiencing (nightmares and flashbacks), Avoidance, Vigilance (hyperarousal), Emotional numbing, and Length of symptoms.

Key Knowledge

What is Post Traumatic Stress Disorder (PTSD)?

According to ICD-11, PTSD may develop following exposure to “an extremely threatening or horrific event or series of events”. In the diagnostic criteria (6B40), its core symptoms are described as:
 
Re-experiencing the traumatic event(s) in the present: vivid intrusive memories, flashbacks, or nightmares accompanied by intense fear or horror. In other words, reliving the event as if it is happening now.
Avoidance of reminders likely to trigger re-experiencing: avoiding thoughts, feelings, people, places, conversations, or situations associated with the trauma.
Persistent sense of threat: hypervigilance, exaggerated startle response, new behaviours to ensure safety (e.g. not sitting with back to the door, repeated checking of windows)
 
Symptoms last for at least several weeks and cause significant impairment. Symptoms typically occur within 3 months of exposure, but can be delayed.

How is Trauma Defined?
There is no universally accepted definition. The diagnostic manuals (DSM and ICD) use an ‘events-based’ definition i.e. an event causing “actual or threatened death, serious injury, or sexual violence” (DSM-V) or an event which is “extremely threatening of horrific” (ICD-11). ICD-11 provides a list of possible traumatic events. This includes direct experiences as well as witnessing or learning of events:
● directly experiencing natural or human-made disasters, combat, serious accidents, torture, sexual violence, terrorism, assault or acute life-threatening illness
● witnessing the threatened or actual injury or death of others in a sudden, unexpected or violent manner
● learning about the sudden, unexpected or violent death of a loved one.
 
The criticism of ‘event-based’ definitions is that they overlook the emotional and cultural aspects of trauma. Some people frame psychological trauma as any event with lasting psychological impact, and the term is increasingly used colloquially to describe everyday difficulties [2]. This is a challenging space to work in.
 
A history of exposure to an event or situation of an extremely threatening or horrific nature does not in itself indicate the presence of PTSD. Many people experience such stressors without developing a disorder.

Differential Diagnosis for PTSD

Complex PTSD:
● This should be considered if all diagnostic requirements for PTSD are met plus severe and persistent problems in affect regulation, beliefs about oneself as diminished, defeated or worthless, accompanied by feelings of shame, guilt or failure related to the traumatic event and difficulties in sustaining relationships. Typically occurs after exposure to repeated traumatic events.

Acute stress reaction:
● Similar features to PTSD but subsides within 1 week after the event

Adjustment disorder:
● Appropriate when triggering event is not extremely threatening or horrific in nature, but PSTD features are present OR
● Triggering event is extremely threatening or horrific in nature but symptoms do not meet the full diagnostic requirements for PTSD

Depression:
● Predominant low mood, intrusive memories are not experienced as occurring in the present

Other Anxiety Disorders (specific phobias, panic disorder):
● Absence of re-experiencing the event e.g. specific phobia can develop after a traumatic event, but memories are experienced as belonging in the past
● Panic attacks can occur in PTSD. They do not come ‘out of the blue’, but instead are triggered by reminders of the traumatic event or in the context of re-experiencing.

Risk Assessment in PTSD

Communication Tips

● It is important to distinguish between re-experiencing and a memory, as this is critical for the diagnosis of PTSD
● You don’t need the patient to describe in detail the traumatic event, this could trigger symptoms e.g. re-living/anxiety
● Validate their distress, e.g. “Many people would find this experience very hard to cope with”
● It can be helpful to explain PTSD as a problem of processing and storing memories, e.g. “During a traumatic event, the brain is in fight or flight mode. This means instead of the memory being stored away, the filing system breaks down.”

CASC Practice Scenarios

Scenario 1: History Taking

Candidate Instructions
You are working in a community mental health team. Mr. David Chen, a 35-year-old firefighter, has been referred by his GP due to difficulties following a traumatic incident at work.
 
Take a focused psychiatric history to establish a diagnosis.

Actor Instructions
You are David Chen, a 35-year-old firefighter with 12 years’ experience. About 18 months ago, you attended a major house fire. Despite your best efforts, a young woman died in the incident. You can still picture her face and the scene vividly. Since then, things have not been the same.
 
You experience vivid, distressing flashbacks of the incident, often triggered by sirens, the smell of smoke, or even seeing children’s toys (as the woman had a child). You have nightmares about the fire several times a week, waking up sweating and anxious.
 
During the day, you sometimes feel as if you’re back at the scene, with the same sounds and smells, and find yourself “zoning out” at work or at home. You feel constantly on edge and find it hard to relax.
You avoid driving past the site of the fire and had asked your supervisor not to send you to callouts in the same neighbourhood.
 
You’ve started avoiding social situations, especially with colleagues, because you worry you’ll “lose it” if the topic comes up.
 
These symptoms started since the incident 18 months ago and have not reduced since then. You feel guilty about the woman’s death, thinking you could have done more, even though your colleagues and superiors have reassured you. You feel disconnected from your partner, friends, and family.
 
You no longer enjoy things you used to, like football, going out, or spending time with your niece and nephew. Your sleep is poor—you have trouble falling asleep and often wake up during the night. You sometimes drink beer in the evenings to help you relax and sleep, but you don’t use illegal drugs.
 
You have never seriously considered suicide or self-harm, but sometimes feel hopeless about things ever improving.
 
You have never had mental health problems before, and there is no family history of mental illness. You live with your partner Alice, who is supportive but worried about you. You have a good relationship with your family, who live nearby. You have not seen a therapist before and are unsure if talking will help, but you agreed to the referral because you feel stuck and want things to change.
 
If the candidate is empathic and builds rapport, you may open up about feeling ashamed and embarrassed, especially as a firefighter who is “supposed to be tough.” You admit you sometimes avoid talking to your partner about your feelings because you don’t want to worry her.
 
If the candidate is rushed or dismissive, you become more withdrawn, give short answers, and may downplay your symptoms.

Feedback for Scenario 1

Scenario 2: History Taking

Candidate Instructions: 
You are working in a community mental health team. Miss Rachel Foster, a 29 year old social worker, has been referred by her GP due to difficulties following an assault. 
 
Take a focused psychiatric history with a view to come to a diagnosis.

Actor Instructions: 
You are Rachel Foster, a 29-year-old social worker. Six months ago, you were physically assaulted while walking home late at night. You were hit over the head and blacked out. Your bag, jewellery and watch were stolen. You went to hospital and luckily, there was no brain injury, only a concussion. However, since that night, your life has changed dramatically.
 
You are plagued by frequent, vivid flashbacks of the attack, sometimes triggered by certain sounds or walking on a pavement. At times, these flashbacks are so intense that you feel as if you are right back in that moment, unable to escape.
 
Sleep has become a struggle. Most nights, you are woken by nightmares about the assault. You wake up in a cold sweat, heart racing, and it takes a long time to feel safe enough to go back to sleep. As a result, you feel exhausted most days and find it hard to focus at work.
 
You have become very wary of your surroundings. You avoid the area where the assault happened completely, even if it means taking a much longer route home. You have also stopped going out alone after dark, and if you have to, you feel constantly on edge, scanning for danger. Loud or unexpected noises make you jump, and you find yourself feeling tense or irritable for no obvious reason. Sometimes, when re-experiencing the assault, you get a feeling that “you are watching yourself in a film.” It is as if things aren’t real.
 
Your mood is low and you’ve lost interest in activities. You sometimes feel hopeless about things ever getting better, but you have not made any plans to harm yourself. You wouldn’t do anything to harm yourself because of your family.
 
If asked about alcohol, you share that you started drinking wine to help you sleep. At first, it was just a glass or two, but now it’s often half a bottle or more each night.
 
You have no past mental health history. You work as a social worker but you are finding it hard to focus on the job. You live alone, but your sister lives nearby.

Feedback for Scenario 2

Scenario 3: Example Video

Candidate Instructions: 
You are working in a community mental health team. Mr. Leon Carter, a 33-year-old man, has been referred after his neighbours reported hearing him screaming at night in his flat. He has a history of psychosis and was admitted to hospital under the mental health act 3 months ago.

Please take a history from Mr Carter.

Authors/Reviewers

Dr Damir Rafi is a Psychiatry Speciality Registrar in forensics, currently working in London.
Dr Sarah Barber is a Psychiatry Registrar, currently taking time out of clinical work to complete a PhD in psychiatric epidemiology.
Dr Mohammad Lalji is a Psychiatry Specialty Registrar. He has previously worked as a medical education fellow in North London.

References and Resources

1. World Health Organization (2022). ICD-11: International classification of diseases (11th revision).
2. National Institute for Health andWorld Health Organization (2022). ICD-11: International classification of diseases (11th revision).
American Psychiatric Association. (2022). Diagnostic and statistical manual of mental disorders (5th ed., text rev.)
3. “Common Definitions” in Mental Health Science: Landscaping Report. Created by Sangath. Accessed here on 22/09/25 [used for section on defining trauma]

Disclaimer:

This article is intended for use as a learning resource for doctors training in Psychiatry in the UK. It is not intended for patients. If you are looking for information about mental health conditions, please visit www.rcpsych.ac.uk/mental-health to find readable, user-friendly and evidence-based information on mental health problems, treatments and other topics written by qualified psychiatrists, with help from patients and carers. If you are looking for help for a mental health condition, please visit https://www.mind.org.uk/ for information about where help is available.
 
The article was written by UK doctors and cross-checked against various published sources (see Reference list). We endeavour to keep information up to date, but it should not be relied on for clinical decision making. Consult local guidelines and senior colleagues whenever you are not sure.