*2.2. Procedures*

Participants answered the questionnaires at the end of 2016, when the law on same-sex civil unions was ye<sup>t</sup> to be approved. The survey was disseminated through the main social networks (e.g., Facebook), posting the advertisement on many LG groups. Furthermore, some Italian non-governmental organization (NGO) representatives involved in the defense of lesbian, gay, bisexual, transgender, and queer rights helped us to carry out a snowball sampling recruitment, asking their affiliates to answer the questionnaire and to disseminate the survey to their personal contacts. No rewards were provided to participate in the survey.

The study was designed with regard to all of the principles of the Declaration of Helsinki on Ethical Principles for Medical Research Involving Human Subjects. According to the EU Regulation 2016/679 "General Data Protection Regulation" (GDPR) and the Code of Conduct for Research in Psychology of the Italian Association of Psychology approved on 27th March 2015, the participants gave their informed consent before completing the questionnaire. Furthermore, in accordance with Italian legislation, privacy was guaranteed through a secure gateway, accessible only to the Principal Investigator, who removed all of the IP addresses before sharing any data with the other researchers.
