Introduction Current obesity assessment tools often capture either fat distribution or overall adiposity, limiting precise risk stratification and individualized management. To address this gap, we developed a dual-dimensional framework for obesity assessment and tiered intervention. Methods Guided by Multidimensional Health Management Theory and the Stages of Change Theory, we constructed the waist-to-height ratio (WHtR)-body fat percentage (BFP) Dual-Dimensional Synergistic Nine-Grid Model. Us