The relationship between conscientiousness and posttraumatic stress disorder among young Chinese firefighters: The mediating effect of perceived social support

•The current study investigated the effect of conscientiousness on posttraumatic stress disorder (PTSD) and its potential mechanism by assessing the young Chinese firefighters.•The participants are not only the professional firefighters, but also the soldiers, which may be different with normal people in the level of PTSD.•What's more, we focus on the influence of perceived social support between the relationship of conscientious and PTSD.•In the current study, we paid attention to the source of perceived social support, and divided it as the support from family and support from others.•Results from this study found that support from others mediated the relationship between conscientiousness and PTSD, while support from family didn't. Previous studies have showed that personality traits are associated with posttraumatic stress disorder (PTSD). The present study investigated the mediating effect of perceived social support between conscientiousness and PTSD in young Chinese firefighters. A total of four hundred and nine firefighters were recruited from a firefighter school in this study. The Chinese big five personality inventory, the PTSD checklist for the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), and perceived social support scale were used to test personality traits, PTSD and perceived social support from family and from others. The results showed that conscientiousness has a significant positive correlation with perceived social support and has a significant negative correlation with PTSD. Moreover, support from others mediated the relationship between conscientiousness and PTSD, while support from family didn't. The results of this study suggest that support from others plays a key role in the relationship between conscientiousness and PTSD of young Chinese firefighters. Clinical implications for trauma interventions and limitations were discussed.