Psychometric properties of the UCLA PTSD reaction index: part I.

This article presents psychometric characteristics of the UCLA PTSD Reaction Index for DSM IV (PTSD-RI) derived from a large sample of children and adolescents (N = 6,291) evaluated at National Child Traumatic Stress Network centers. Overall mean total PTSD-RI score for girls was significantly higher as compared with boys. Age-related differences were found in that overall mean total PTSD-RI scores and within sex groups were higher among those aged 7-9 years and 16-18 years. There were no significant differences in mean total PTSD-RI scores across racial/ethnic groups. The PTSD-RI total scale displayed good to excellent internal consistency reliability across age ranges, sex, and racial/ethnic groups (α = .88-.91). Correlations of PTSD-RI scores with PTS subscale scores on the TSCC-A for the entire sample and within sex, age, and ethnic/racial groups provided evidence of convergent validity, although not discriminant validity. In contradistinction to previously reported 4-factor models, an exploratory factor analysis revealed 3 factors that mostly reflected the underlying dimensions of PTSD in DSM IV. PTSD-RI scores were associated with increased odds ratios for functional/behavior problems (odds ratio [OR] = 1-1.80). These findings are striking in light of the wide range of trauma exposures, age, and race/ethnicity among subjects.