Measurement properties of a multicultural weight-specific quality-of-life instrument for children and adolescents

PURPOSE: To evaluate the psychometric properties of a new multicultural weight-specific quality-of-life (QOL) measure for children and adolescents–Youth Quality-of-Life Instrument–Weight module (YQOL-W). METHODS: Twenty-five candidate items were administered to 443 children and adolescents between 11 and 18 years of age, of whom 53% were female, 33% were white, 30% were African American and 37% were Mexican American. Thirty-four percent had a healthy body mass index (BMI), 20% were overweight and 46% were obese. RESULTS: Twenty-one of the original 25 candidate items were retained in the final instrument. Exploratory and confirmatory factor analyses (CFA) resulted in a one-factor (21 items, alpha = 0.97) and a three-factor model including a Self factor (4 items, alpha = 0.90), a Social factor (11 items, alpha = 0.95) and an Environment factor (5 items, alpha = 0.90). CFA found the three-factor model had better model fit (P < 0.05). Both the one-factor and three-factor scores were negatively correlated with BMI and the Children’s Depression Inventory and positively correlated with generic quality of life, all at the P < 0.05 level. The 1-week test–retest intra-class correlation coefficients were 0.73 for Social, 0.71 for Self, 0.73 Environment and 0.77 for the one-factor model. CONCLUSIONS: The YQOL-W shows good reliability and validity for assessing weight-specific QOL in children and adolescents.