Crowd-sourcing optimized abdomen CT protocols from 908,000 examinations in a large radiation dose registry

Question Can we identify best-practice imaging protocols from a large CT registry, to offer clinicians a blueprint for optimizing radiation dose in routine abdomen CT? Findings Protocols were grouped into clusters using average acquisition parameters. Across clusters, patient size-adjusted radiation dose varied 486-1382 mGy-cm. Lowest-dosed protocols had one phase and low kVp. Clinical relevance We used crowd-sourcing and k-means clustering to identify routine abdomen CT protocols that achieve lowest radiation dose, offering a playbook for protocol design from real clinical practice. Non-indicated phases were the greatest driver of excessive radiation dose.