Mode: Web-paper interviews, 2 parts
Population, unit of observation: Individuals among the permanent resident population of Switzerland, aged 18 and over (no upper age limit), living in private households (and speaking either German, French or Italian)
Simple random sample, drawn on national level by the Swiss Federal Statistical Office from the SRPH (Population register: Stichprobenrahmen für Personen- und Haushaltserhebungen)
Individuals are invited through postal letters and up to 3 reminders, paper is offered with the second reminder (push-to-web design). Respondents to Part 1 are invited to participe also in Part 2 in the mode of their first answer (for details, refer to the Survey Report).
- Gross sample size 6008
- Net sample size (without ineligibles): 5991
- Valid interviews Part 1: 3349 (AAPOR response rate=55,9%)
- Valid interviews Part 2: 2328 (69,5% of Part 1 interviews)
Design:
- Cross-sectional, annual survey since 2018 (bi-annual before), most background questions are repeated, the ISSP modules are mostly repeated every 10 years
- Fieldwork period: 26.02.2021-12.07.2021
Fieldwork institute: FORS, Lausanne
No weighting, all weight=1, according to the sample design (all respondents have the same probability to be selected); for nonresponse-bias, please refer to the analysis in the Survey Documentation Report
