Objectives:
The changes in the structure of PTSD symptoms introduced in the DSM-5 classification require the use of an appropriate measurement tool. For this purpose, the PTSD Checklist (PCL-5) was constructed and popularized. In the presented studies, the psychometric properties of the Polish version of PCL-5 were assessed. In addition, referring to the controversy regarding the conceptualization of PTSD, various indicators of the fit of five PTSD structure models were checked based on our own research.

Methods:
People (N = 1035) who experienced various traumatic events participated in the anonymous research. All completed PCL-5 and another questionnaires used to assess the validity of PCl-5.

Results:
The psychometric properties of the Polish version of PCL-5 are satisfactory. In the differential diagnosis the optimal point of discrimination is the result of ⩾ 33. The CFA results showed that all tested PTSD models met the basic fit criteria. The four-factor model explained 58% of the variance, including changes in arousal and reactivity of 36%.

Conclusions:
PCL-5 is a reliable and accurate tool for PTSD measurement. It is used for the initial diagnosis of PTSD. The conducted analyzes, despite demonstrating the diagnostical utility of PCL-5, do not indicate ultimately favor a single PTSD dimensionality model.