Abstract
Background: Given the prevalence of scoliosis, it is essential for residents in Physical and Rehabilitation Medicine to develop proficiency in evaluating spinal radiographs, particularly in measuring the Cobb angle. This education and training study aimed to define the minimum educational requirements for residents to achieve competency in Cobb angle measurement with acceptable inter- and intra-operator variability, as reported in the literature. Methods: In this ethics-approved study, Physical and Rehabilitation Medicine residents measured Cobb angles and the Risser index using specialized software on 30 different spinal X-rays, with oversight to ensure consistency and eliminate bias. Results: The data revealed that 44.4% of residents achieved the target accuracy for primary Cobb angles (<3.6°), but only 11.1% did so for secondary curves. For intra-operator error, 88.9% of residents met the target for primary curves, but only 11.1% achieved the target for secondary curves. The Risser index showed minimal deviation across all participants. Conclusions: These findings highlight that mastering Cobb angle measurement is challenging and generally requires more than 20 different measurements for inter-operator reliability and over 30 repetitions for intra-operator reliability, particularly when secondary curves are included.