Functional impairment as defined by the DSM-IV and the DSM-5 was assessed by five questions measuring how distressing it was when they had PTSD symptoms on a 5-point scale (1 = Not at all, 5 = Extremely), and whether PTSD symptoms produced problems with employment and in their personal life, relationships, or school. Functional impairment was positive if PTSD symptoms were quite a bit or extremely distressing for them, or they reported problems in one or more of the four areas of functioning.
