Validating Sizing Them Up: A parent-proxy weight-related quality-of-life measure, with community-based children

Int J Clin Health Psychol. 2018 Jan-Apr;18(1):81-89. doi: 10.1016/j.ijchp.2017.10.001. Epub 2017 Nov 22.

Abstract

Background/Objective: A weight-related Quality of Life (QoL) questionnaire elicits parents' perceptions to understand the impacts of weight on children's QoL. Sizing Them Up, a parent-proxy of a weight-related instrument, is a proper measure for the purpose, but its psychometric properties have not been validated on a non-clinical child population. This study aimed to thoroughly examine the psychometric properties of the Sizing Them Up on a non-clinical child population. Methods: Children from Taiwan (M age = 11; SD = 1.02; N = 236) filled out a weight-related QoL instrument (Sizing Me Up) while their parents completed Sizing Them Up and two generic QoL instruments. Confirmatory factor analysis (CFA), concurrent validity, and known-group validity were conducted. Results: CFA supported the factor structure of Sizing Them Up. The concurrent validity of the Sizing Them Up total score was satisfactory: r = .46 to .53 with other QoL instruments. Known-group validity was supported as obese children had significantly lower Sizing Them Up total score than did normal-weight and underweight children. Conclusions: We extended the use of Sizing Them Up from clinically obese children to a community-based sample of underweight as well as overweight children. Healthcare providers may use Sizing Them Up to measure the weight-related QoL for children.

Antecedentes/objetivo: Un cuestionario que relaciona peso y calidad de vida (CV) estimula la percepción de los padres para comprender los impactos del peso sobre la CV de los niños. Sizing Them Up es un instrumento para padres, relacionado con el peso, pero sus propiedades psicométricas no se han validado en población infantil no clínica. Este estudio examina minuciosamente dichas propiedades en una población infantil no clínica. Método: Niños de Taiwán (M edad = 11,00; DT = 1,02; N = 236) completaron el Sizing Me Up, mientras sus padres completaron este mismo instrumento y otros dos genéricos de CV. Se realizó análisis factorial confirmatorio (CFA), y se examinó la validez concurrente y validez de grupo conocido. Resultados: El CFA apoya la estructura factorial del Sizing Them Up. La validez concurrente fue satisfactoria. La validez de grupo conocido fue apoyada, ya que los niños obesos obtuvieron una puntuación en Sizing Them Up significativamente menor que los niños de peso normal o bajo peso. Conclusiones: Los proveedores de atención médica pueden utilizar Sizing Them Up para medir la CV relacionada con el peso de los niños.

Keywords: Child; Community; Instrumental study; Parent; Weight-related quality of life.