Factorial invariance of the Satisfaction with Life Scale in adolescents from Spain and Portugal

Background: The Satisfaction with Life Scale is one of the most widely used scales to measure the global cognitive judgment of satisfaction with one's life. Method: This study assesses the equivalence of the SWLS across Spanish and Portuguese adolescents, using multi-sample Confirmatory Factor Analysis. Participants were Spanish (N = 2183) and Portuguese (N = 4082) junior high school. Results: The results provide high support for the internal consistency of both the Spanish and Portuguese versions of this scale. The results also showed that factor structure, factor loadings, could be considered invariant across groups. However, the full scalar invariance between Spanish and Portuguese samples was not found, with the intercept for SWLS item 5 varying across countries. Conclusions: Similar findings have also been found in other cross-national studies with this scale. Implications of the findings are discussed and we conclude that the Spanish and Portuguese versions of the SWLS can be used for cross national comparisons with Spanish and Portuguese adolescents.