Simple vs complex. I agree with dr. Pappas. Simple ptsd may occur after 1 or few traumatic event such as a rape or a motor vehicle accident. Complex ptsd often has many contributors & traumas. For instance: base is regularly motarred, lack of contact with loves ones, concern about the safety of subordinants, heat, constant hum of noisy generators, death of battle buddies etc. The trauma is ingrained in many ways.
Long-term trauma. Complex ptsd can arise after long-term, as opposed to shorter term (but still upsetting) traumas.The victim is generally held in a physical or emotional state of captivity. In these situations the victim is under the control of the perpetrator and unable to flee. Examples might be concentration or pow camps; childhood physical, emotional, & sexual abuse, etc. After- effects are more pervasive.