ICD-11 Complex PTSD in US National and Veteran Samples: Prevalence and Structural Associations with PTSD.

The eleventh edition of the International Classification of Diseases (ICD-11) is under development and current proposals include major changes to trauma-related psychiatric diagnoses, including a heavily restricted definition of posttraumatic stress disorder (PTSD) and the addition of complex PTSD (CPTSD). We aimed to test the postulates of CPTSD in samples of 2695 community participants and 323 trauma-exposed military veterans. CPTSD prevalence estimates were 0.6% and 13% in the community and veteran samples, respectively; one-quarter to one-half of those with PTSD met criteria for CPTSD. There were no differences in trauma exposure across diagnoses. A factor mixture model with two latent dimensional variables and four latent classes provided the best fit in both samples: classes differed by their level of symptom severity but did not differ as a function of the proposed PTSD versus CPTSD diagnoses. These findings should raise concerns about the distinctions between CPTSD and PTSD proposed for ICD-11.