Socio-demographic variables include, for example, age, sex, education, migration background and ethnicity, religious affiliation, marital status, household, employment, and income. Different index variables are formed on the basis of socio-demographic variables. They include, for example, socio-economic status, which combines information on education and income. Socio-demographic details are often used to describe realised samples and to determine sampling error.
The contributions devoted to socio-demographic variables provide an overview of available survey instruments or address the measurement of individual socio-demographic variables.