Validity, reliability and factor analysis of the Polish version of the Peritraumatic Distress Inventory.

Aim. Evaluating validity and reliability of the Polish version of the Peritraumatic Distress Inventory (PDI) and conducting factor analysis of this tool. Material and methods. A cross-sectional study encompassed 100 employees of the Polish emergency medical system. They completed the author's questionnaire, the Polish version of the Impact Event Scale-Revised and the 13-item PDI validated in this study. Results. Cronbach's alpha coefficient for the entire scale, ultimately including 12 items, is 0.77. A three-factor structure of the tool has been demonstrated, explaining 60.04% of the variance. This analysis revealed moderate to high values of the factor loadings of all items which form subscales with the exception of the fifth subject. On this basis it was decided to reject the fifth item. Cronbach's alpha for factor 1 (Loss of control and arousal) is 0.75, for factor 2 (Negative emotions) -0.77 and for factor 3 (Feeling of threat) -0.68. A strong positive correlation between distress and severity of symptoms of posttraumatic stress disorder (r = 0.70, p < 0.01) was shown. Additionally, distress strongly and positively correlated with the various symptoms of PTSD: intrusion, arousal and avoidance. Conclusions. The Polish version of the PDI is a relevant and reliable distress assessment tool.