Post traumatic stress disorder (PTSD) is differentiated from all other disorders by:

C i.e. Recall of events and avoidance of similar experiences in PTSD- PTSD arises as response to traumatic event (criteria A) that is characterized by persistent re-experience (criteria B), persistent avoidance and numbness (C), hyperarousal (D), of > 1 month duration (criteria E) causing significant distress & impaired functioning (criteria F)Q. The onset may be delayed (6 months to years after event).- PTSD arises as a delayed/protracted response to an exceptionally stressful or catastrophic life event or situation which is likely to cause pervasive distress in almost any person (eg. disaster, war, rape, toure, serious accident). It may develop even after 6 months to years after stressorQ.- PTSD is characterized by peristent/recurrent intrusive distressing recollections of stressful event either in flashbacks (images, thoughts or perceptions), dreams, reliving experiences, illusions, hallucinations or distress/ physiological reactivity on exposure to reminders of traumatic events. There is marked (persistent) avoidance of stimuli/events or situations that arouse recollection of stressful events and increased arousal (hyperarousal) and numbing of general responsivenessQ.Paial amnesia for some aspects of stressful events, anhedonia (inability to experience pleasure) and alexithymia (characterized by inability to identify & aiculate feelings) may be present.