Measurement invariance of the Satisfaction With Life Scale (SWLS)by country, gender and age.

BACKGROUND Although the Satisfaction With Life Scale (SWLS) is the most widely used instrument to measure life satisfaction with its validation having been carried out across ages and countries, few studies have analyzed SWLS measurement cross-cultural invariance with adolescents. With respect to Spanish adolescents, measurement invariance across gender has not been found and the one-factor structure has not been confirmed in Mexican adolescents through Structural Equation Modeling. METHOD The main purpose of this study was to explore the measurement invariance of the SWLS in a sample of 701 adolescents (Mage = 14.93, SD = 1.83), 47.1% boys and 52.9% girls, from two different countries: Spain (74.2%) and Mexico (25.8%). A multigroup confirmatory factorial analysis is performed to test the invariance of the unifactorial structure. of SWLS with respect to the variables country, gender and age. RESULTS Results support a single-factor structure as well as the internal consistency of the SWLS. Similarly, the tests of measurement invariance support its strict invariance regarding country and gender, and strong invariance regarding age. CONCLUSIONS These results suggest that the SWLS is a useful single-factor measure of life satisfaction in Spanish and Mexican adolescents.