Measurement invariance of the Satisfaction with Life Scale by gender, age, marital status and educational level

The Satisfaction with Life Scale (SWLS) has shown strong evidence of acceptability, reliability, validity and invariance for gender, whereas there is mixed evidence of invariance by culture and age and the literature has not explored the roles of marital status and educational level. The SWLS should be invariant by marital status and educational level to be able to compare scores between groups. We aimed to explore the invariance of the SWLS by marital status and educational level.

A convenience sample of 726 Spanish adults participated in a survey. We tested a one-factor model using confirmatory factor analysis. We tested the configural, metric and scalar invariance of the factorial structure of the SWLS by gender, age, marital status and level of education.

The results show a scalar invariance by gender and educational level and a partial scalar invariance by marital status. Women and individuals in a relationship show greater subjective well-being while no differences are observed among people with different educational levels.

The SLWS is valid for comparisons between genders, age, educational levels but not for marital status. It is essential to verify its invariance to interpret mean differences and significance values appropriately.