The official diagnosis needs to meet the following requriements, as indicated by each symptom cluster--which I've identified by letter--(according to the DSM-IV-TR and the ICD-10):A. exposure to a traumatic event in which both of the following were present:1. you experience, witness or was confronted with an event or events that involve actual or threatened death or seriuos injury, or a threat to the physical integrity of the self.2. your response involves intense fear, helplessness or horror. (Children may express this via disorganized or agitated behavior).B. The traumatic event is persistently re-experienced in one or more of the following ways:1. recurrent, intrusive and distressing recollections of the event, including images, thoughts, or perceptions.2. recurrent distressing dreams of the evetn3. acting or feeling as if the traumatic event were recurring (i.e., a sense of reliving the event, which can be through illusions, hallucinations, and/or dissociative flashback episodes).4. intense psychological distress at exposure to internal or external cues that symbolize or resemble an aspect of the event.5. physiological reacitivity on exposure to internal or external cues that symbolize or resemble an aspect of the traumatic event.C. Persistent avoidence of stimuli associated with the traumatic event and numbing of general responsiveness, as indicated by three or more of the following:1. efforts to avoid thoughts, feelings, or conversations associated with the trauma.2. efforts to avoid activities, places, people that arouse recollections of the trauma.3. inability to recall an important aspect of the trauma.4. markedly diminished interest or participation in activities the individual used to engage in.5. feeling of detachment or estrangement from others.6. restricted range of affect (e.g., unable to have loving feelings).7. sense of a foreshortened future.D. Persistent symptoms of increased arousal, as indicated by 2 or more:1. difficulty falling or staying asleep2. irritability or outburst of anger3. difficulty concentrating4. hypervigilance5. exaggerated startle responseE. These disturbances must occur for more than 1 monthF. These disturbances cause significant distress or impairment in social, occupational, or other important areas of functioningNOTE:As a psychologist, I see a lot of PTSD or symptoms similar to PTSD. It can be tricky to accurately diagnose, even for trained professionals. As a consequence, it tends to be over diagnosed. If you think you have this problem you should see a psychologist (perferrably one with a Ph.D. or Psy.D.). The other thing to recognize is that much of the research on this topic suggests that these symptoms will remit after 3 to 6 months, especially if you have a supportive social network who you are comfortable talking to and can openly discuss your feelings about the trauma.