Development and Validation of a Comprehensive Obesity Assessment Tool: Integrating Lifestyle, Body Image, and Past...

Young adulthood is a critical period for the establishment of lifelong health behaviours. However, increasing sedentary lifestyles, suboptimal dietary patterns, and weight-related body image concerns contribute to the growing burden of obesity in this age group. A comprehensive and culturally sensitive assessment tool is needed to capture these multidimensional factors. This study aimed to develop and psychometrically validate a questionnaire assessing lifestyle behaviours, weight-related body image concerns, and past weight management strategies among young adults (YAs).

A mixed-method design was employed. Item generation was informed by literature review and focus group discussions, followed by expert review for content validity and pilot testing for face validity. Construct validity was assessed using exploratory factor analysis (EFA; n = 302) and confirmatory factor analysis (CFA; n = 151) within a structural equation modelling framework. Internal consistency was evaluated using Cronbach's alpha, and test-retest reliability (n = 102) was assessed using intraclass correlation coefficients (ICC) with 95% confidence intervals.

The final questionnaire comprised 30 items across three domains: lifestyle and associated barriers (17 items), weight-related body image concerns (6 items), and past weight management (7 items). Factor analyses supported a three-domain structure with satisfactory model fit indices. Internal consistency ranged from 0.72 to 0.86 across domains. Test-retest reliability demonstrated high stability (ICC range: 0.951-0.970).

The developed questionnaire demonstrates satisfactory psychometric properties and may serve as a practical tool for assessing obesity-related behavioural and psychosocial factors among young adults in clinical and research settings.