d identify shared risk factors for PTSD only and comorbidity of PTSD and anxiety. Individuals who experienced Dongting Lake flood in 1998 were enrolled in this study using stratified and systematic random sampling method. Information on social support, personality traits, PTSD, and anxiety was collected using self-report questionnaires. The intensity of exposure to the flood was measured by some questions. Logistic regression analyses were used to identify factors associated with PTSD only an...
