Letter to the Editor concerning "Radiation-free 3D assessment of back height differences via three-dimensional depth sensing in adolescent idiopathic scoliosis: prospective, single-center, observational study" by S. Chen, et al. (Eur Spine J [2025]; doi:10.1007/s00586-025-09154-8).

This letter discusses a study on radiation-free 3D assessment of adolescent idiopathic scoliosis. While the study provides valuable insights, we raise three methodological and statistical considerations: (1) the risk of false positives from multiple comparisons and the suggestion of FDR correction; (2) the recommendation to supplement with Spearman's correlation for assessing potential nonlinear relationships; and (3) the proposed biomechanical mechanism whereby measurement posture may influence correlations in thoracolumbar/lumbar curves. The intent is to provide constructive feedback for refining the study.