These childhood and adult exposures to traumatic events result in an increased risk for the development of PTSD .Mueser et al .(2004) reviewed the prevalence of PTSD in seven studies of patients with SMI and found the rates to between 14% and 43%. The number of exposure to trauma, and traumatization during childhood correlated with the severity of PTSD symptoms in these studies. Cusack et al.(2006) found a lifetime PTSD prevalence rate of 19-30 % among patients seeking treatment in a community mental health centre. In studies using the gold standard Clinician Administered PTSD scale (CAPS), Grubaugh et al . (2011) reported a prevalence rate of 13-46 % in patients with SMI.