AI-Based Personalized Digital Management for High-Risk Pulmonary Nodule Follow-up

The goal of this pragmatic clinical trial is to learn whether AI-based personalized digital management can help patients with high-risk pulmonary nodules complete appropriate follow-up care. The study will include adults aged 40 years or older whose pulmonary nodules were identified on chest CT scans already performed at the hospital for clinical care, health examinations, or other reasons. The hospital's AI-based lung nodule evaluation system will be used to identify nodules classified as high risk. Patients who have already completed follow-up or entered an active pulmonary nodule management pathway will not be included. The main question this study aims to answer is: \- Does personalized digital management increase the proportion of patients who complete appropriate pulmonary nodule follow-up within 16 weeks after randomization compared with usual care? Researchers will compare personalized digital management with usual care. Participants will be randomly assigned in a 1:1 ratio to one of the following groups: * The personalized digital management group will receive individualized information about the pulmonary nodule and recommendations for appropriate follow-up through the hospital's official WeChat account. * The usual care group will not receive the study-specific personalized digital message. Participants in both groups may continue to receive routine clinical care. Participants will: * Provide electronic informed consent * Answer a brief questionnaire about pulmonary nodule care received outside the hospital and selected health information, including smoking history * Continue their usual medical care * Allow researchers to review relevant hospital records to determine whether pulmonary nodule follow-up was completed The study will not arrange an additional initial chest CT solely for research purposes. Appropriate follow-up may include specialist evaluation, follow-up chest CT, PET/CT, tissue sampling, surgery, or a documented clinical decision tha