recent case-control study has analyzed the records of 223 adolescent athletes (72% males) who sought care for low back pain (LBP) between 2015 and 2019. Subjects were retrospectively classified as suffering from LBP caused by spondylolysis (if ''MRI showed a high-intensity signal at the pars interarticularis. . . regardless of duration of pain''), or suffering from nonspecific (NS) LBP (if ''no remarkable changes were found in the x-ray and MRI''). CART analysis was used to develop an algorithm to distinguish one group from the other based on personal and clinical features. 1 We would like to point out that:1. This design assumes that (''acute'') spondylolysis always causes pain, and that images of spondylolysis rule out the diagnosis of NSLPB. Basic science and clinical evidence contradicts these assumptions. 2,3 2. Study's retrospective design, lack of definition of ''acute'' pain, impossibility to reliably identify pain duration and its relation to imaging findings, sample size, characteristics and sex imbalance, and statistical methods used, also challenge the generalizability of results.Therefore, we think that, before focusing on improving the sensitivity of the algorithm, as the authors suggest, further studies with more solid methods should confirm its validity and explore its generalizability.