- Directly experiencing the traumatic event
- Witnessing, in person, the event as it occurred to others
- Learning that the traumatic event occurred to a close family member or close friend. In cases of actual or threatened death of a family member or friend, the event must have been violent or accidental.
- Experiencing repeated or extreme exposure to aversive details of the traumatic event
Presence of one or more of the following intrusion symptoms associated with the traumatic event, beginning after the traumatic event happened can occur for individuals with trauma or post-traumatic disorder:
- Recurrent, involuntary and intrusive distressing memories of the traumatic event
- Recurrent, distressing dreams in which the content and/or effect of the dream are related to the traumatic event.
- Dissociative reactions (flashbacks) in which the individual feels or acts as if the traumatic event were recurring
- Intense or prolonged psychological distress at exposure to internal or external cues that symbolize or resemble an aspect of the traumatic event
- Marked physiological reactions to internal or external cues that symbolize or resemble an aspect of the traumatic event
In children older than six, repetitive play, trauma-specific reenactment or frightening dreams without recognizable content may occur in which themes or aspects of the traumatic events are expressed.