Early trauma response
Acute stress disorder after a motor accident
Acute stress disorder is an early trauma-related psychiatric diagnosis with defined DSM-5-TR criteria and timing. It is not the same as ordinary distress and it is not automatically PTSD. Under the current NSW CTP Regulation, acute stress disorder is expressly a threshold injury.
Motor accident mechanism
What can happen in a motor accident?
Rear-end crash
A sudden rear collision may produce intrusive memories, startle, dissociation and immediate driving avoidance.
Side-impact crash
A side impact may cause acute fear, sleep disturbance and re-experiencing during the first weeks.
Motorcycle fall
A motorcycle fall may expose the rider to serious threat, injury and distressing hospital treatment.
Pedestrian impact
A pedestrian may experience acute trauma from seeing the vehicle approach, impact and emergency response.
Injuries and diagnoses that may follow
- acute stress disorder meeting DSM-5-TR criteria
- an ordinary acute stress response below diagnostic threshold
- early PTSD-like symptoms that require duration and criteria review
- associated panic, depressive or dissociative symptoms
- a later diagnosis such as PTSD requiring fresh assessment
Symptoms to record accurately
- intrusive memories, dreams or flashback-like reactions
- negative mood or emotional numbing
- dissociation, altered sense of reality or poor recall
- avoidance of reminders
- hyperarousal, startle, sleep and concentration difficulty
Urgent health warning
Immediate assistance is required for suicidal thoughts, inability to remain safe, severe dissociation or acute mental health crisis.
Clinical evidence
What objective findings and records matter?
The report should identify the trauma exposure, symptom groups, timing, impairment and differential diagnoses. The early timing is important because PTSD and adjustment disorder have different diagnostic requirements even though acute stress disorder and adjustment disorder share the current threshold classification.
| Record or test | What it can establish | What it cannot establish alone |
|---|---|---|
| Early GP or emergency record | Documents timing, acute symptoms, safety concerns, sleep, dissociation and referrals. | Shock or distress immediately after a crash does not by itself establish acute stress disorder. |
| Psychologist or psychiatrist interview | Maps DSM-5-TR criteria, duration, impairment and differential diagnoses. | A trauma questionnaire alone does not establish the diagnosis. |
| Treatment chronology | Shows symptom course and whether the condition resolved, persisted or changed diagnosis. | Treatment duration does not automatically change the threshold classification. |
| Functional evidence | Records early self-care, travel, work, relationships and concentration effects. | Acute disruption should not be assumed to be permanent. |
Part 5 classification
Is the injury threshold or non-threshold?
Regulation clause 4(2) expressly includes acute stress disorder as a threshold injury. If symptoms persist and a clinician later diagnoses PTSD or another recognised psychiatric illness, that later diagnosis must be supported by its own criteria and causation evidence. The acute stress label does not automatically convert.
Evidence consistent with a threshold classification
- acute stress disorder
- ordinary distress that does not meet a recognised illness
- early trauma symptoms without a settled diagnosis
- adjustment disorder
Evidence that may support a non-threshold injury
- a later properly established recognised illness other than the Regulation exceptions
- PTSD supported by the required duration and symptom criteria
- major depressive disorder or another recognised condition with accident causation
- organic brain-related behavioural injury assessed neurologically
Separate questions: threshold injury classification does not set WPI, and receiving statutory benefits does not automatically create a common law damages entitlement.
Part 6 permanent impairment
How is WPI assessed for this injury?
Acute stress disorder is usually an early diagnosis, so permanent impairment should not be assumed during the acute phase. If a permanent psychiatric condition is later assessed, the psychiatrist applies PIRS to the current recognised diagnosis and function, not to the worst early symptoms.
| Assessment question | Applicable method | Important limit |
|---|---|---|
| Acute diagnosis | Clauses 5.10-5.12 require psychiatric diagnosis using DSM-5-TR and the Regulation controls threshold classification. | The early diagnosis is not a permanent impairment score. |
| Later diagnosis | Clause 6.213 requires the current recognised diagnosis and criteria to be stated before PIRS. | A transition to PTSD or another disorder must be medically explained. |
| Current function | If permanent impairment is assessed, PIRS Tables 6.11-6.17 apply to current sustainable function. | The assessor does not rate the acute period as though it were permanent. |
- Separate early diagnosis from later diagnosis and prognosis.
- Use current function, not the most intense immediate aftermath, for any permanent assessment.
- Address treatment response and whether the condition resolved.
- Keep physical and psychiatric WPI separate.
- Do not infer WPI from the number of acute symptoms.
The six PIRS tables
Psychiatric WPI is assessed across six areas of function. A psychiatrist assigns a class from the evidence in each area; the classes are not percentages and are not simply added or averaged.
| Guidelines table | Function assessed | Examples of useful evidence |
|---|---|---|
| Table 6.11 | Self-care and personal hygiene | washing, dressing, meals, medication and ordinary personal routines |
| Table 6.12 | Social and recreational activities | participation, initiation, frequency, support and withdrawal from usual activities |
| Table 6.13 | Travel | independent travel, public transport, driving, unfamiliar routes and support needed |
| Table 6.14 | Social functioning and relationships | family, friends, communication, conflict, isolation and capacity to maintain relationships |
| Table 6.15 | Concentration, persistence and pace | task completion, errors, supervision, breaks, reliability and sustained mental effort |
| Table 6.16 | Adaptation | response to work-like demands, stress, change, attendance and pre-injury roles where relevant |
Verified calculation example from the Guidelines
If the six supported class ratings are 2, 2, 3, 3, 4 and 4, the median class is 3 and the aggregate score is 18. Table 6.17 gives 22% WPI before any valid treatment adjustment. This demonstrates the calculation only. It is not a way to estimate WPI from symptoms without a psychiatrist’s assessment.
What does not establish the result by itself?
- shock immediately after the crash
- a trauma checklist alone
- early work absence as permanent impairment
- duration alone without diagnostic review
- adding physical WPI
Accident-specific examples
Acute symptoms resolve with short-term treatment
The injury remains a threshold diagnosis and may produce no permanent psychiatric impairment, even though early treatment was appropriate.
Symptoms persist and PTSD is later diagnosed
The later clinician should identify PTSD criteria, duration and causation. The new diagnosis is assessed on its evidence rather than assumed from acute stress disorder.
Early dissociation after a head impact
Brain injury and acute stress may overlap. The medical evidence should distinguish altered consciousness or post-traumatic amnesia from psychiatric dissociation.
Claim file preparation
Evidence checklist
Assessment source
Acute stress disorder threshold source
Assessment source: Motor Accident Injuries Regulation 2017 clause 4(2)-(3); Motor Accident Guidelines v10.1 clauses 5.10-5.12 and, for any later permanent psychiatric assessment, 6.201-6.228.
Threshold injury: Acute stress disorder is expressly a threshold injury. A later different recognised psychiatric illness requires its own supported diagnosis and causation analysis.
What the assessor checks
- express threshold classification
- DSM-5-TR diagnostic approach
- separation of acute and permanent assessment
- PIRS for any later permanent psychiatric impairment
What does not establish the result by itself
- shock
- screening score
- early incapacity
- combined WPI
Official sources
Related NSW CTP guides
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Frequently asked questions
- Is acute stress disorder a threshold injury?
- Yes. Regulation clause 4(2) expressly includes it as a threshold injury.
- Is acute stress disorder the same as PTSD?
- No. They have different DSM timing and diagnostic requirements. A later PTSD diagnosis must be independently supported.
- Does threshold status prevent treatment?
- Not automatically. Classification and entitlement to reasonable treatment are separate scheme questions.
- Can early symptoms be used for permanent WPI?
- Permanent WPI is based on the current stable condition and function, not the most intense acute period.
- What if altered awareness may have been concussion?
- The brain-injury and psychiatric evidence should be reviewed together so post-traumatic amnesia or altered consciousness is not confused with dissociation.