title: Peritraumatic Behavior Questionnaire - Observer Rated: Validation of the objective version of a measure for combat-related peritraumatic stress.
abstract: OBJECTIVE
  To validate the first third-person-rated measure assessing combat-related peritraumatic stress symptoms and evaluate its psychometric properties and war-zone applicability.
  
  
  METHODS
  The valid assessment of peritraumatic symptoms in the theater of military operations represents a significant challenge in combat-related, mental health research, which mainly relies on retrospective, subjective self-report ratings. This longitudinal observational study used data from actively deployed troops to correlate third-person observer ratings of deployment peritraumatic behaviors [Peritraumatic Behavior Questionnaire - Observer Rated (PBQ-OR)] collected on a bi-monthly basis with post-deployment (1-wk follow-up) ratings of the previously validated PBQ self-rate version (PBQ-SR), and (3-mo follow-up) clinician assessed and self-report posttraumatic stress disorder (PTSD) symptoms (Clinician Administered PTSD Scale, PTSD Checklist). Cronbach's alpha (α) and correlation coefficients were calculated to assess internal reliability and concurrent validity respectively.
  
  
  RESULTS
  Eight hundred and sixty male Marines were included in this study after signing informed consents at pre-deployment (mean age 23.2 ± 2.6 years). Although our findings were limited by an overall sparse return rate of PBQ-OR ratings, the main results indicate satisfactory psychometric properties with good internal consistency for the PBQ-OR (α = 0.88) and high convergent and concurrent validity with 1-wk post-deployment PBQ-SR ratings and 3-mo posttraumatic stress symptoms. Overall, later PBQ-OR report date was associated with higher correlation between PBQ-OR and post-deployment measures. Kappa analysis between PBQ-OR and PBQ-SR single items, showed best agreement in questions relating of mortal peril, desire for revenge, and experience of intense physical reactions. Logistic regression demonstrated satisfactory predictive validity of PBQ-OR total score with respect to PTSD caseness (OR = 1.0513; 95%CI: 1.011-1.093; P = 0.02).
  
  
  CONCLUSIONS
  Since no comparable tools have been developed, PBQ-OR could be valuable as real-time screening tool for earlier detection of Service Members at risk.
authors.affiliation: Agorastos Agorastos, Abigail C Angkaw, Dewleen G Baker, Veterans Affairs Center of Excellence for Stress and Mental Health (CESAMH), San Diego, CA 92161, United States.
authors.forename: Agorastos
authors.initials: A
authors.lastname: Agorastos
authors.affiliation: Agorastos Agorastos, Abigail C Angkaw, Dewleen G Baker, Veterans Affairs Center of Excellence for Stress and Mental Health (CESAMH), San Diego, CA 92161, United States.
authors.forename: Abigail C
authors.initials: AC
authors.lastname: Angkaw
authors.affiliation: Agorastos Agorastos, Abigail C Angkaw, Dewleen G Baker, Veterans Affairs Center of Excellence for Stress and Mental Health (CESAMH), San Diego, CA 92161, United States.
authors.forename: Heather E
authors.initials: HE
authors.lastname: Johnson
authors.affiliation: Agorastos Agorastos, Abigail C Angkaw, Dewleen G Baker, Veterans Affairs Center of Excellence for Stress and Mental Health (CESAMH), San Diego, CA 92161, United States.
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Hansen
authors.affiliation: Agorastos Agorastos, Abigail C Angkaw, Dewleen G Baker, Veterans Affairs Center of Excellence for Stress and Mental Health (CESAMH), San Diego, CA 92161, United States.
authors.forename: Camille V
authors.initials: CV
authors.lastname: Cook
authors.affiliation: Agorastos Agorastos, Abigail C Angkaw, Dewleen G Baker, Veterans Affairs Center of Excellence for Stress and Mental Health (CESAMH), San Diego, CA 92161, United States.
authors.forename: Dewleen G
authors.initials: DG
authors.lastname: Baker
keywords: Assessment; Combat; Dissociation; Military service; Peritraumatic reaction; Posttraumatic stress disorder; Stress; Trauma