Answer to the Letter to the Editor of M. A. Potts concerning “Providence nighttime bracing is effective in treatment for adolescent idiopathic scoliosis even in curves larger than 35°” by Simony A, Beuschau I, Quisth L, et al. [Eur Spine J; (2019): https://doi.org/10.1007/s00586-019-06077-z]