<prompt> Which of the following factors is the most impoant predictor of development of Post-Traumatic Stress Disorder PTSD in a 30-year-old man who has just been involved in a road traffic accident?Death of a friend in the accidentHis age and genderHistory of panic disorderHistory of substance abuse  <response>: Severity of event or accident is the most impoant predictor for development of PTSD. 