Reply to the Letter to the Editor of S. Birch et al. concerning “Clinical practice guidelines for the management of nonspecific low back pain in primary care: an updated overview” by Oliveira CB, Maher CG, Pinto RZ, Traeger AC, Lin CWC, Chenot JF, van Tulder M, Koes BW (2018) Eur Spine J; https://doi.org/10.1007/s00586-018-5673-2