The present study included 2987 college students who experienced direct danger due to a deadliest disaster in modern time, a total of 14.1% of college students met the criteria for PTSD diagnosis one year following the 2008 Wenchuan earthquake. The students who were injured during the traumatic event, those lost their first degree relative, and those confronted with dead bodies had high risks of developing PTSD. Male students were more likely to express PTSD. However, the students who received psychological tutorship were less prone to express PTSD.
The prevalence of PTSD reported in victims of earthquake trauma ranges from 10% to 67%, depending on the nature of the trauma, investigation time and the people that are sampled. In Northridge, California, three months after 6.7 Richter scale earthquake, the incidence of PTSD in the disaster population was 13% . Ten months following the 1999 earthquake in central Taiwan, PTSD was observed in only 10.3% of the population . However, PTSD prevalence rate reached 66.7% in adolescents from the finding of Ziaaddini et al. . Kuo and colleague  found that at one year after the Taiwan earthquake, the PTSD rate in survivors was 16.5%, but the investigation on disaster victims with house damage two years after the earthquake had shown that the incidence rate of PTSD reached 20.9%. The above demonstrated that adolescents are more prone than adults to express PTSD.
Age may impact the course of the disorder, children and adolescents are more emotionally vulnerable to the devastating effects of a disaster due to their developmental status . The prevalence of PTSD reached 66.7% in high school students of Bam a city located in Southern Iran, ten months after an earthquake with a magnitude of 6.3 on the Richter scale . We conducted the survey one year after Wenchuan earthquake, and found that 420 developed typical PTSD symptoms in 2987 college students, with a PTSD prevalence rate of 14.1%. The difference amongst previous studies may be due to the different methodologies, sample population and the time of earthquake. The high school students surveyed by Ziaaddini et al. were asleep when earthquake happened. However, we conducted the study among college students who had stronger cognitive skills, the students were attending classes when the event occurred, the teachers could support them emotionally by sharing the horrible experience and encourage them to be strong.
Females were significantly more susceptible to serious psychiatric morbidity than males in some studies conducted on PTSD in post disaster period [10, 11], but the differences in the prevalence of PTSD between gender are less clear in adolescents . Our study showed that the incidence rate of PTSD in male was higher than that in the female students. Compared to male students, female students were more willing to acknowledge symptoms and more prone to express their symptoms , they would also demonstrate higher average levels of symptoms and seek help more often. A bigger proportional of female students thus received early psychological intervention, resulting in a lower incidence of PTSD.
PTSD prevalence rate was significantly high in severely disastered area, and it was a significant factor associated with PTSD. Preexisting psychopathology and prior exposure to trauma are important individual factors in trauma response [14, 15], characteristic of one’s exposure to trauma also significantly influence response. The college students in our study had been living in a safe and peaceful environment, they did not have any practical experience in dealing with big trauma. As victims and on-spot witnesses, the subjects were direct exposures, thus they were more likely to develop severe PTSD.
Poststressor factors significantly influence the severities of PTSD symptomatology . Poststressor factors including the recovery environment, coping methods and treatment provide strong impacts on adjustment following exposure to trauma. Psychological interventions play an important role in the effective treatment of PTSD. We supplied the students who expressed PTSD useful behavioral and cognitive skills to enhance their capacity to manage PTSD-related symptoms. A relatively low rate of PTSD was noted in those who got psychological help following earthquake. Social support is among the strongest predictive factors of PTSD in children and adolescents and may serve as a buffer during and after trauma. For the students who presented with early PTSD symptoms and who have risk factors of PTSD, it is extremely necessary to provide more social support and pertinent psychological help to reduce the occurrence of severe PTSD and prevent chronic PTSD.