*2.1. Participants*

A questionnaire was administered cross-sectionally on an online survey platform, which participants (both psychiatric patients and healthy controls) accessed via a designed link. The respondents were 82 Italian psychiatric patients, living in two rehabilitation communities in the Lazio region during the COVID-19 lockdown, and 106 healthy control subjects, recruited online and randomly chosen from a larger sample on the basis of mean age. The two communities are accredited by the National Health Service and provide healthcare assistance through qualified personnel 24 h per day. Various professional figures work closely with psychiatric patients within the community: psychiatrists, educators, psychologists, nurses and social assistants. During the lockdown, all the professionals continued to work in the community guaranteeing psychiatric patients' continuity of care and treatment. In both communities, an attempt was made to maintain a link with the patients' affections and families through remote communication systems, strengthening the Internet connection and helping psychiatric patients with video calls. Several meetings have been held within the community between the mentioned professionals in order to organize specific therapy groups for the psychiatric patients. Positive reinforcement techniques were used to encourage participation in therapy groups to prepare the patients to face social isolation and emotional flattening.

The psychiatric patients were aged 18 years or older and had been diagnosed with at least one psychotic disorder; healthy controls were aged 18 years or older and had no psychiatric diagnosis. All participants voluntarily responded to the anonymous survey and indicated their informed consent. The procedures were clearly explained, and participants could interrupt or quit the survey at any point without providing explanation. As regards the questionnaire administered to psychiatric patients, the first items were intended for the community administrators who helped patients respond to the measure. The remaining items were administered for patient self-report.

Five psychiatric patients and six healthy controls were excluded from the analysis because they did not complete the entire survey. The final sample consisted of 177 participants. The psychiatric patient sample comprised 77 participants: 51 males (*Myears* = 47.29; *SD* = 13.26) and 26 females (*Myears* = 45.27; *SD* = 12.03), aged 22–73 years, with a mean age of 46.61 (*SD* = 12.81). Most psychiatric patients did not have children and were either retired or recipients of state support. The healthy control sample comprised 100 participants: 50 males (*Myears* = 48.38; *SD* = 12.79) and 50 females (*Myears* = 44.42; *SD* = 9.81), aged 20–69 years, with a mean age of 46.40 (*SD* = 11.52). No significant difference was found between groups in age [*F* (1,176) = 0.013, *p* = 0.909], while significant differences were found in gender [χ*<sup>2</sup>* (1) = 4.679, *p* = 0.031] and education [*F* (1,176) = 14.796, *p* ≤ 0.001] (see Table 1).



Data were collected between April and May 2020, before the end of the lockdown period in Italy. Expedited ethics approval was obtained from the Institutional Board of the Department of Human Neuroscience, Faculty of Medicine and Dentistry, "Sapienza" University of Rome (IRB-2020-6), in conformity with the principles of the Declaration of Helsinki.

Descriptive statistics are reported in Table 1.

Most psychiatric patients (93.5%) received training and education on COVID-19 and its transmission by the referred community, hence we assessed patients' knowledge about the COVID-19 pandemic using three items (i.e., "How did you become aware of the spread of COVID-19?"; "What is COVID-19?"; "Did you participate in community training sessions on this health emergency?"). Each of these items enabled more than one response option to be indicated. Furthermore, the first two items were also administered by the healthy control group, in order to assess where they had retrieved information about the virus and their awareness about it. Possible responses to the first item differed between groups, since the psychiatric patients were living in the rehabilitation communities and had contact with the operators. Table 2 reports the response frequency of these items.


**Table 2.** Descriptive statistics of the sample, in regard to knowledge about COVID-19.

Note. \* indicates responses/questions administered only to the psychiatric patients.
