Development and Validation of a s Standardized Video-Based Assessment of Movement Quality in Breast Cancer Survivors
Seung Hyun Chung, Heoung Su Kim, Ha Ra Jeon, Mi Ri Suh, So Young Ahn, Jin Ah yoon, So Young Lee, Yu Hui Won and Eun Joo Yang*
ABSTRACT
Objective: To develop and validate a standardized, video-based movement quality assessment for breast cancer survivors, termed the Rehabilitation Movement Assessment Protocol (ReMAP) by examining its construct validity and internal reliability.
Design: Cross-sectional validation study.
Setting: Outpatient rehabilitation settings.
Participants: Seventy breast cancer survivors able to ambulate independently.
Methods: Seventy breast cancer survivors completed the movement quality assessment at baseline, consisting of sequential, unfamiliar functional tasks designed to emphasize real-time sensorimotor control. Movement quality metrics-including postural stability (mediolateral center-of-mass sway), coordination (lateral correction rate, movement smoothness), movement efficiency (energy ratio), and motor control (trajectory variability)-were derived from RGB video using pose estimation. Construct validity was evaluated by examining Pearson and Spearman correlations between kinematic metrics and clinical reference measure, including the Timed Up and Go test. Within-session internal reliability was assessed using intraclass correlation coefficients (ICC [3,1]) across repeated task segments. Measurement error indices, including standard error of measurement and minimal detectable change at the 95% confidence level, were calculated.
Results: Movement quality metrics demonstrated substantial inter-individual variability without floor or ceiling effects. Associations with clinical reference measures were generally weak, supporting the conceptual distinction between movement quality and performance-based outcomes. Coordination-related correction behavior showed a significant monotonic association with Timed Up and Go performance (Spearman ρ = 0.295, p = 0.015). Internal reliability varied across domains, with excellent reliability for coordination, good reliability for motor control, moderate reliability for movement efficiency and smoothness, and lower reliability for postural sway. Measurement error indices provided interpretable thresholds for measurement precision.
Conclusion: The ReMAP Assessment provides a feasible and objective approach to quantifying movement quality in breast cancer survivors. Demonstrating acceptable construct validity and domain-specific internal reliability, this assessment captures qualitative aspects of movement behavior that are not reflected by conventional performance-based mobility tests and may enhance functional assessment in oncology rehabilitation.
