Els van Meijel

12 Chapter 1 | General introduction or indirect exposure to aversive details of the trauma. PTSD includes symptoms of re- experiencing (i.e. intrusive thoughts, nightmares, emotional distress after traumatic reminders), avoidance of trauma-related stimuli (i.e. thoughts, feelings, reminders), negative alterations in cognitions and mood (i.e. negative affect, decreased interest in activities), increased arousal (i.e. irritability or aggression, difficulty concentrating or sleeping), resulting in substantial distress or impairment in functioning (APA, 2013). Acute Stress Disorder (ASD) can be diagnosed if symptoms persist for no longer than one month after the traumatic event; PTSD can be diagnosed if symptoms persist for longer than one month (APA, 2013). Posttraumatic stress in children After an accident, children may develop acute stress symptoms. These symptoms disappear spontaneously in the majority of the children in the weeks following traumatic events, but 8% to 14% develop posttraumatic stress disorder (PTSD) following unintentional injury (Alisic et al., 2014) and up to 18% develop severe posttraumatic stress symptoms (PTSS) (Landolt, Vollrath, Timm, Gnehm, & Sennhauser, 2005). According to the National Institute for Clinical Excellence (NICE, 2018), up to 30% of children who attend an emergency department for a traumatic injury will develop PTSD. PTSD is a debilitating psychiatric disorder, often involving the development of co-morbid disorders (Stallard, Salter, & Velleman, 2004) and affecting children’s functioning and physical recovery from injury (Kahana et al., 2006). Posttraumatic stress symptoms in injured children are associated with poorer functional recovery one year or more after the injury (Kassam-Adams et al., 2013). Since ASD or PTSD at a subsyndromal level can also result in substantial impairment in functioning, it is also appropriate to evaluate and treat children reporting clinically significant persistent PTSS (Gold, Kant, & Kim, 2008). Although the long-term impact of traumatic events can be substantial, research on long-term PTSD after accidental injury is scarce and involves follow-up periods of 1.5 years or less. In a literature review to determine the prevalence of PTSD among children 8 years to 18 years injured in traffic (Olofsson, Bunketorp, & Andersson, 2009), only one study with a 2-month to 18-month follow-up study was included. This study reported 14% PTSD in victims of motor vehicle accidents. In a meta-analytic study on changes in the prevalence of child posttraumatic stress disorder, the follow-up period