Date of Award

January 2018

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Steven M. Southwick


The proposed study aims to characterize the course of subthreshold PTSD and to identify predictors of conversion of subthreshold PTSD to full PTSD over a four-year period using a nationally representative survey of U.S. veterans. The National Health and Resilience in Veterans Study (NHRVS) is a four-year prospective cohort study of 3,157 US veterans. This web-based, nationally representative survey consists of 3 waves: Wave 1 was conducted in 2011 (n=3,157), Wave 2 in 2013 (n=2,157, 68.3%) and Wave 3 in 2015 (n=1,538, 48.7%). Trauma-exposed veterans identified with subthreshold PTSD at Wave 1 are followed through Waves 2 and 3, and their PTSD status is ascertained (i.e., remain subthreshold, develop full PTSD, remit from subthreshold). The rates of conversion are compared to trauma-exposed veterans without subthreshold or full PTSD at Wave 1, which serve as the control. Results of this study suggest that subthreshold PTSD is a prodrome to PTSD, with a 7.5 times higher likelihood of progressing to incident PTSD longitudinally, and five factors are identified to be linked to this progression: dispositional optimism, number of traumas, physical difficulties, loneliness, and cognitive impairment. This study may inform prevention and treatment efforts designed to mitigate risk for the development of full PTSD in U.S. veterans and other trauma-affected populations. Raising awareness on the subthreshold manifestation of this disorder may hinder the more costly, more chronic, and more difficult to treat development of PTSD.


This thesis is restricted to Yale network users only. It will be made publicly available on 06/25/2100