Last reviewed: 25 Sep 2021
Last updated: 30 Apr 2019



History and exam

Key diagnostic factors

  • exposure and response to trauma
  • intrusion symptoms
  • avoidance symptoms
  • negative alterations in cognitions and mood
  • alterations in arousal and reactivity

Other diagnostic factors

  • depression
  • alcohol or substance misuse
  • anxiety

Risk factors

  • serious accident
  • witness of school violence or domestic violence
  • natural disaster
  • terrorist attack
  • torture
  • combat exposure
  • traumatic brain injury
  • sudden death of loved one
  • molestation
  • rape
  • victimization by attacker
  • previous trauma
  • multiple major life stressors
  • low social support
  • history of mental disorder
  • history of drug and alcohol abuse
  • female sex
  • younger age

Diagnostic investigations

1st investigations to order

  • PTSD Checklist
  • PTSD Checklist for DSM-5 (PCL-5)
  • Impact of Event Scale - Revised (IES-R)
  • Davidson Trauma Scale (DTS)
  • Trauma Screening Questionnaire (TSQ)
  • SPAN

Investigations to consider

  • Clinician-Administered PTSD Scale (CAPS)
  • Clinician-Administered PTSD Scale for DSM-5 (CAPS-5)
  • Structured Clinical Interview for the DSM-IV Axis I Disorders (SCID PTSD Module)
  • PTSD Symptom Scale-Interview Version (PSS-I)

Treatment algorithm



Stanley Zammit, MA, BM BCh, MRCPsych, PhD

Professor of Psychiatric Epidemiology

Centre for Academic Mental Health

School of Social and Community Medicine

University of Bristol


Clinical Senior Lecturer & Honorary Consultant Psychiatrist

Institute of Psychological Medicine and Clinical Neurosciences

Cardiff University




SZ declares that he has no competing interests.

Mathew Hoskins, MBBCh, MSc, MRCPsych

Consultant Psychiatrist and Clinical Teaching Fellow

Institute of Psychological Medicine and Clinical Neurosciences

School of Medicine

Cardiff University




MH is an author of references cited in this topic.

Catrin Lewis, BSc, PhD

Research Associate

National Centre for Mental Health

Institute of Psychological Medicine and Clinical Neurosciences

School of Medicine

Cardiff University




CL declares that she has no competing interests.


Dr Stanley Zammit, Dr Mathew Hoskins, and Dr Catrin Lewis would like to gratefully acknowledge Dr Neil P. Roberts, Dr Jonathan I. Bisson, and Dr Steve Wood, previous contributors to this topic.


NPR is a member of the research team that developed a web-based guided self-help program to treat PTSD. NPR has also received grant funding for research related to PTSD and undertaken systematic reviews, meta-analyses, randomized controlled trials, and other research in the traumatic stress field that may be referred to in this work. JIB and SW declare that they have no competing interests.

Peer reviewers

Mort Rubinstein, MD

Deputy Associate Chief of Staff

Mental Health

VA New York Harbor Healthcare System

Clinical Associate Professor

New York University School of Medicine

New York



MR declares that he has no competing interests.

Neil Greenberg, MD, MRCPsych

Surgeon Commander

Royal Navy

Defence Professor of Mental Health, Visiting Professor of Psychiatry, and Co-Director

Academic Centre for Defence Mental Health

King's College London




NG has been principal investigator on studies with research funding greater than 6 figures USD. NG is a director of a company providing early intervention training for traumatic stress (the company does not provide PTSD treatment services).

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