The impact of different diagnostic criteria on PTSD prevalence: A comparison of PTSD prevalence using the DSM-IV and ICD-10 PTSD-criteria on a population of 242 Danish social work students

The diagnostic criteria for PTSD have undergone several changes in the last two decades. This may in part explain the great variance in PTSD prevalence found in existing research. The objective of this study is to investigate the influence of different diagnostic criteria and different combinations of criteria on PTSD prevalence. A sample of 242 Danish social work students (M =29.2 years) completed a list of potentially traumatizing events, major life events and the Harvard Trauma Questionnaire. A considerable difference in PTSD prevalence as a result of different diagnostic criteria of PTSD was found. Future meta-analyses and reviews of PTSD prevalence must take into account the impact of changing criteria on prevalence. Clinicians also need to address this issue when assessing PTSD.