Posttraumatic stress disorder (PTSD) and major depressive episode (MDE) are frequent and disabling consequences of surviving severe injury. The majority of those who develop these problems are not identified or treated. The aim of this study was to develop and validate a screening instrument that identifies, during hospitalization, adults at high risk for developing PTSD and/or MDE. Hospitalized injury patients (n = 527) completed a pool of questions that represented 13 constructs of vulnerability. They were followed up at 12 months and assessed for PTSD and MDE. The resulting database was split into 2 subsamples. A principal-axis factor analysis and then a confirmatory factor analysis were conducted on the 1st subsample, resulting in a 5-factor solution. Two questions were selected from each factor, resulting in a 10-item scale. The final model was cross-validated with the 2nd subsample. Receiver-operating characteristic curves were then created. The resulting Posttraumatic Adjustment Scale had a sensitivity of .82 and a specificity of .84 when predicting PTSD and a sensitivity of .72 and a specificity of .75 in predicting posttraumatic MDE. This 10-item screening index represents a clinically useful instrument to identify trauma survivors at risk for the later development of PTSD and/or MDE.