MacDonald Franklin OSI Research Centre Armour, C, Elhai, J D, Richardson, D, Ractliffe, K, Wang, L & Elklit, A 2012, ' Assessing a Five Factor Model of PTSD: Is Dysphoric Arousal a Unique PTSD Construct Showing Differential Relationships with Anxiety and Depression? ', Journal of Anxiety Disorders, vol. 26, no. 2, pp. 368-376 . https://doi.org/10.1016/j.janxdis.2011.12.002