**2. Experimental Section**

### *2.1. Participants and Procedure*

In order to generate a representative sample of healthcare workers, quota sampling was used. Quota sampling is a non-probabilistic sampling method in which the population of healthcare workers was divided in equally exclusive subgroups. First, we selected the subgroups of healthcare workers with regard to five criteria: gender, age, types of healthcare professions, years of service, and a level of

education. Second, we identified the proportions of these subgroups and then selected subjects from the various subgroups on a basis of these proportions. The aim was to assemble a sample that would have the same proportions of individuals and be representative of the entire population of healthcare workers with respect to the abovementioned characteristics. The final sample consisted of 226 healthcare personnel working in hospitals, outpatient clinics, and medical laboratories in southern Poland during the first few months of the coronavirus pandemic (March–May 2020), and who were consequently exposed to the associated health risks. The group comprised the following professions: doctors (*n* = 51), nurses (*n* = 113), laboratory technicians (*n* = 22), aides and assistants (*n* = 29), and physiotherapists (*n* = 11). Of the participants, 58.8% were female and 41.2% were male. Their average age was 37.36 (SD = 13.59). All were employed either full-time or part-time.

Participants were recruited in hospitals, outpatient clinics, and medical laboratories, with the aim of acquiring a representative sample of healthcare personnel. They were provided with information regarding the purpose and rules of participation and were asked to fill in an online or printed version of the questionnaire. A research assistant was available in case any additional information was requested. The University Ethics Board accepted the research material and procedure.
