For our baseline analysis, we used data from the 2017 Czech Mental Health Study (CZEMS), which is described in detail elsewhere (Winkler et al., 2018a; Formánek et al., 2019). Briefly, eligibility criteria were the same as in 2020 survey, but the data were collected using the PAPI method and two-staged sampling, with a random sample of participants being selected from a random group of voting districts. The response rate was 75% and the final sample of 3306 respondents was representative of the Czech general population in terms of age, gender, education and region of residence. The description of the 2017 sample is provided in online Supplementary Table 1.