* The individual has been exposed to or threatened with death, serious injury, or sexual violation: by direct experience or by witnessing a traumatic event; upon learning about a violent or accidental death of a close friend or family member; or by extreme or repeated exposure to the effects of a traumatic event, such as emergency workers encountering humn remains.
* Intrusive symptoms associated with the traumatic event will be experienced, such as disturbing dreams, or feeling that the event is recurring while awake; uncontrolled memories of the event; extreme physical reactions or mental distress upon being reminded of the trauma.
* Individuals will avoid internal and/or external reminders of the trauma.
* At least two changes to mood or thought processes will occur, such as feelings of disconnection, continual negative emotions and ongoing difficulty in experiencing positive emotions, extreme and disproportionate negative expectations; reduced interest in activities, being unable to remember certain aspects of the traumatic event.
* Changes to reactive behaviour will occur, and individuals will display two or more of the following symptoms: recklessness, aggression, hypervigilance, inability to concentrate, difficulty sleeping, an exaggerated startle response.
* Symptoms began or worsened after the traumatic event(s) and continued for at least 1 month, causing significant difficulty in functioning.
* Symptoms cannot be explained by the effects of other mental or medical disorders, drug abuse, or medication.