Subjective Well-Being Scale, short version (EBS-8): Revalidation, measurement invariance and Item Response Theory

Abstract

The Subjective Well-Being Scale (EBS-20) and its short version (EBS-8) were developed and validated to measure life satisfaction and positive affect in a Spanish-speaking population. The aim of the present study was to obtain additional evidence of validity for the EBS-8. To this end, the scale was applied in three successive studies to a total of 2259 Mexicans aged 12 to 81 years. The results of the first study allowed us to confirm its unifactorial structure (CMIN/DF = 2.336; CFI = .996; RMSEA = .047) and its adequate reliability (α = .958, ω = .957); in the second its measurement invariance by sex, social group and age was tested (Δχ2 p >. 05, ΔCFI < .004, ΔRMSEA < .014); and in the third study it was found, by calibrating its items under IRT, that the scale satisfactorily estimates the construct assessed (a > 1.69; b1 between-2.78 and-2.35). From the psychometric indices obtained, it is concluded that the EBS-8 is an excellent brief instrument constructed in Spanish to assess subjective well-being in adolescents, young people, adults and older adults.