Ultrasound Screening for Early Detection of Breast Cancer in Elderly Women: a Mixed Cluster-Individual RCT

This is a multicenter, open‐label, mixed cluster‐individual randomized controlled trialconducted in Jiangsu Province, China. A total of 82,440 elderly women aged 65‐80 yearswill be enrolled and assigned to either the ultrasound active screening group or theroutine health management group. Communities with limited screening capacity will berandomized as clusters, while communities with individual screening conditions willrandomize participants individually.The primary endpoint is the absolute difference in the diagnosis rate of early‐stagebreast cancer between the two groups within 2 years of follow‐up. In pilot communities ofthe screening group, an ultrasound AI system will be deployed synchronously to verify itsdiagnostic performance, homogenization effect on primary care physicians, and healtheconomic value. All clinical diagnosis and endpoint adjudication are based on manualultrasound reports; AI results are only used for retrospective scientific research and donot interfere with clinical decision‐making.