BackgroundRecent signs of fraudulent behaviour in spine RCTs have queried the integrity of trials in the field. RCTs are particularly important due to the weight they are accorded in guiding treatment decisions, and thus, ensuring RCTs’ reliability is crucial. This study investigates the presence of non-random baseline frequency data in purported RCTs published in spine journals.MethodsA PubMed search was performed to obtain all RCTs published in four spine journals (Spine, The Spine Journal, the Journal of Neurosurgery Spine, and European Spine Journal) between Jan-2016 and Dec-2020. Baseline frequency data were extracted, and variable-wisepvalues were calculated using the Pearson Chi-squared test. Thesepvalues were combined for each study into study-wisepvalues using the Stouffer method. Studies withpvalues below 0.01 and 0.05 and those above 0.95 and 0.99 were reviewed. Results were compared to Carlisle’s 2017 survey of anaesthesia and critical care medicine RCTs.ResultsOne hundred sixty-seven of the 228 studies identified were included. Study-wisepvalues were largely consistent with expected genuine randomized experiments. Slightly more study-wisepvalues above 0.99 were observed than expected, but a number of these had good explanations to account for that excess. The distribution of observed study-wisepvalues was more closely matched to the expected distribution than those in a similar survey of the anaesthesia and critical care medicine literature.ConclusionThe data surveyed do not show evidence of systemic fraudulent behaviour. Spine RCTs in major spine journals were found to be consistent with genuine random allocation and experimentally derived data.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00586-023-07813-2.