Confirmatory Factor Analysis of Sizing Me Up: Validation of an Obesity-Specific Health-Related Quality of Life Measure in Latino Youth

Objectives This study aims to validate an obesity-specific health-related quality of life (HRQOL) measure, Sizing Me Up (SMU), in treatment-seeking Latino youth. Pediatric obesity has been associated with reduced HRQOL; therefore, valid measures are important for use in diverse populations that may be at increased risk for obesity and related comorbidities. Methods Structural equation modeling tested the fit of the 5-subscale, 22-item SMU measure in Latino youth, 5-13 years of age, with obesity (N = 204). Invariance testing was conducted to examine equivalence between Latino and non-Latino groups (N = 250). Results SMU achieved acceptable fit in a Latino population [chi(2) = 428.33, df = 199, p < .001, Root Mean Squared Error of Approximation = 0.072 (0.062-0.082), Comparative Fit Index = 0.915, Tucker-Lewis Index = 0.901, Weighted Root Mean Square Residual = 1.2230]. Additionally, factor structure and factor loadings were invariant across Latino and non-Latino groups, but thresholds were not invariant. Conclusions SMU is a valid measure of obesity-specific HRQOL in treatment-seeking Latino youth with obesity.