Factorial structural analysis of the Spanish version of WHOQOL-BREF: an exploratory structural equation model study

The purpose of this study was to analyze the factor structure of the abbreviated Spanish version of the World Health Organization Quality of Life (WHOQOL-BREF; WHOQOL Group in Psychol Med 28(3): 551-558, 1998b) questionnaire in a sample of individuals from several Spanish-speaking countries. The data were based on a sample of 1,972 undergraduates from nine Spanish-speaking countries. Within the framework of a somewhat wider research protocol, they were administered the WHOQOL-BREF. The data were initially analyzed using a confirmatory factor analysis, which yielded a poor fit to the four-factor theoretical model. Based on these results, the best solution was estimated assuming structural invariance across countries. The data showed a four-factor structure that differed slightly from the model proposed. This four-factor model was subsequently analyzed using exploratory structural equation modeling (ESEM; Asparouhov and Muth,n in Struct Equ Model 16(3): 397-438, 2009) to obtain the invariant structure across countries and an estimation of the relation between the four latent factors. The results obtained allowed us to establish that the factor structure of WHOQOL-BREF maintains the four-factor solution hypothesized for a Spanish-speaking population, although the solution has a different and more complex configuration than the original one with a clear tendency toward non-orthogonality of the latent factors. As has been suggested by some studies on the application of ESEM, it is reasonable to think that the ESEM approximation is a useful approach for conducting the factor analysis of instruments measuring complex psychological phenomena.