Who Develops Posttraumatic Stress Symptoms Following a Bank Robbery? A National Cohort Study

Each year, numerous bank robberies take place worldwide. Even so, only few studies have investigated the psychological sequelae of bank robbery and little is known about the risk factors associated with the development of posttraumatic stress disorder (PTSD) following this potentially traumatic event. Knowledge about risk factors related to PTSD may allow for preventive measures to be taken against the development of PTSD and reduce the large cost associated with the disorder. Furthermore, the few existing studies are characterized by several limitations such as the use of small convenience or self-selecting samples. To overcome these limitations, we investigated the estimated prevalence rate of acute stress disorder (ASD) and PTSD and predictors of PTSD severity in a Danish cohort study of all bank employees exposed to robbery during one year (N = 614). A total of 450 employees (73 %) filled out the first questionnaire a week after the robbery (T1). Of these, 371 employees (82 %) filled out the second questionnaire six months after the robbery (T2). Results showed that 11.1% of the participants suffered from ASD (T1) and 6.2 % suffered from PTSD (T2). The results of a hierarchical regression analysis showed that 51 % of the variance in PTSD severity could be explained with only peritraumatic dissociation, ASD severity, and negative cognitions about self being significant predictors. However, interpretation of the role of peritraumatic dissociation in the regression model was hampered by a statistical artifact (negative suppression). The strongest predictors of PTSD severity were ASD severity followed by negative cognitions about self. This indicates that victims with high levels of ASD are at increased risk of developing PTSD following bank robbery. Thus, screening for PTSD following bank robbery should focus on ASD severity. In accordance with a cognitive model of PTSD and the DSM-5, the results show that posttraumatic negative cognitions about self also seem to play a pivotal role in the development of PTSD following bank robbery. This indicates that it may be possible to develop preventive cognitive interventions targeted at bank employees that focus on changing negative cognitions about self.