This study aimed to evaluate the predictive factors of the emergence of complete PTSD and subsyndromal PTSD (defined as individuals exposed to a traumatic event with at least one psychopathological impact, such as hyperarousal, avoidance or persistent re-experiencing) following a motor vehicle accident (MVA).We recruited 155 adult MVA patients, physically injured and admitted to trauma service, over two years. In the week following the accident, patients were asked to complete questionnaires assessing their social situation (sex, age, marital and employment status, prior MVA or trauma), comorbidity (MINI), distress (PDI) and dissociation (PDEQ) experienced during and immediately after the trauma. An evaluation using the CAPS was conducted six months after the trauma to assess a possible PTSD.At six months, 25.8% of the participants developed subsyndromal symptoms and 7.74% developed complete PTSD. The three symptoms that best discriminated the groups were dysphoric emotion, perceived life threat and dissociation. Logistic regression results showed that the strongest predictor of PTSD was the perceived life threat. In addition, a dimensional approach to the results revealed significant correlations between (1) peritraumatic distress and persistent re-experiencing or hyperarousal and (2) dissociation score and avoidance strategy. The presence of a prior traumatic event reinforces avoidance strategies.Our results stress that peritraumatic factors (especially the perception of a life threat) are good predictors of PTSD development. A dimensional perspective allows better identification of psychological complications following an MVA.