*2.1. General Procedure*

This cross-sectional, observational research is part of a larger study on the neurobiological inheritance of PTSD, which was approved by the Ethics Committee of our University (Comissão de Ética para a Sa úde do Centro Hospitalar de São João/Faculdade de Medicina da Universidade do Porto, approval number: CES-138/08). Having received a complete written and verbal description of the study, all the participants gave their written informed consent. Interaction with the participants was carried out in a university setting and was solely performed by the same researcher and was carried out individually during one appointment. No financial compensation was paid for participating in this study, although paymen<sup>t</sup> for transport to the university was provided.
