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Details on data collection per canton (Corona Immunitas, Switzerland, 2020–2021). Abbreviations: GR, Graubünden: SG, St. Gallen; TI, Ticino; ZH, Zurich. In TI, SG and GR, participants completed questionnaires following a rolling enrolment. Therefore, participants were invited to the second assessment 3 months after the first assessment.
