VALIDITY AND INVARIANCE OF THE SATISFACTION WITH LIFE SCALE ACCORDING TO MENTAL HEALTH LEVELS IN LATIN AMERICAN MEDICAL STUDENTS

Introduction: Life satisfaction is an important indicator of subjective well-being. Objective: To evaluate the factorial structure and measurement invariance of the Satisfaction With Life Scale (SWLS) among Latin American medical students according to mental health status. Methods: A cross-sectional study was conducted with 344 medical students from five Latin American countries. Life satisfaction was measured using the SWLS, and mental health was assessed with the 12-item General Health Questionnaire, based on which participants were classified into two groups. Confirmatory factor analysis was performed using a diagonally weighted least squares estimator with robust standard errors. Factor loadings, internal consistency using Cronbach's alpha and McDonald's omega, global fit indices, and multigroup measurement invariance through configural, metric, scalar, and residual models were also calculated. Results: The multigroup model showed adequate global fit, with χ² = 49.3, RMSEA = 0.067, SRMR = 0.055, CFI = 0.989, and TLI = 0.992, supporting the suitability of the unidimensional model. Factor loadings ranged from 0.546 to 0.825 among students with poor mental health, with α = 0.753 and ω = 0.771, and from 0.675 to 0.842 among those who reported good mental health, with α = 0.813 and ω = 0.819. The latent factor variances were 0.298 and 0.524, respectively. The invariance analysis showed minimal differences between models, with ΔCFI≤ 0.01 and ΔRMSEA≤ 0.015, supporting factorial equivalence between the two groups. Conclusions: The SWLS showed adequate psychometric properties and factorial invariance according to mental health status among Latin American medical students.