A critical consideration in the treatment of PTSD is whether the traumatic event producing the PTSD reaction is a Type I or Type II trauma. In short, a Type I trauma is an unexpected, isolated traumatic event of relatively short duration (such as, a motor vehical accident, a single incident of physical or sexual assault, a natural disaster), that often involves fear of dying during the event itself. Recovery from a Type I traumatic event i soften relatively rapid, especially if the trauma victim does not suffer from any kind of permanent or lasting physical injury. By contrast, a Type II trauma is more long-standing in nature and often involves a series of expected, repeated traumas, such as ongoing sexual or physical abuse or torture., that result in a negatively altered schematic view of oneself, others, and the world. Type II traumas often develop into more complex and chronic PTSD responses that are linked to other psychological disorders, including higher rates of depression, anxiety and panic disorders, eating disorders, substance abuse, chronic relationship difficulties and long-standing characterological disturbances evidenced by emotional lability, suicidality, and self-abusive behaviors.
Mervin Smucker (2012).