The five-item Satisfaction With Life Scale (SWLS; Diener et al., 1985) is one of the most commonly used instruments for measuring life satisfaction. Many studies using the classical test theory (CTT) have confirmed its good psychometric properties, namely validity, internal consistency, and test-retest reliability (Pavot et al., 1991; Pavot & Diener, 1993; Lucas et al., 1996).
However, results regarding its dimensionality and equivalence testing between countries or different social groups vary (Clench-Aas et al., 2011; Emerson et al., 2017). In the Czech Republic, except for two non-representative studies, the SWLS has not been tested so far (Lewis et al., 1999; Navrátil & Lewis, 2006).
The aim of this presentation is to present the results of a study focusing on testing the psychometric properties of the Czech version of the SWLS using CTT and item response theory (IRT) methods, as well as testing its equivalence between different social groups (in terms of gender, age and education). The analysis will be performed on data from a representative sample of the Czech online population aged 18 to 69 years old in 2021 collected using the CAWI method.