Pietrzak, R.H., Feder, A., Singh, R., et al. (2014). Trajectories of PTSD Risk and Resilience in World Trade Center Responders: An 8 Year Prospective Cohort Study. Psychological Medicine. 44(1): 205-219.
The authors studied the factors associated with posttraumatic stress disorder (PTSD) symptoms in World Trade Center first responders. They found that prior psychiatric history, Hispanic ethnicity, severity of WTC exposure and WTC-related medical conditions had the strongest relationships with PTSD; greater levels of education and family and work support were protective factors.