Synthetic electronic health record (EHR) data generation has emerged as a potential solution to balancing clinical data accessibility with patient privacy, using generative artificial intelligence to simulate tabular, longitudinal, and textual health records without exposing identifiable patient information. This critical review, informed by PRISMA-ScR methodology, examines studies published between 2017 and 2025 focusing on generative models for synthetic EHR creation, with particular attention to privacy risks, data fidelity, downstream task utility, and ethical or regulatory considerations. A total of 67 studies were included after systematic screening, showing a dominance of GAN-based approaches alongside growing use of diffusion models and large language models in recent years, although privacy assessment and benchmarking practices remain inconsistent. Overall, the evidence suggests that while synthetic EHR data can facilitate data sharing, research, and model development, achieving a balance between realism, utility, and privacy remains challenging, as high statistical fidelity does not necessarily translate into clinical usefulness and strong downstream performance does not ensure adequate privacy protection.
Generative artificial intelligence (AI), including GANs, VAEs, and diffusion models, is increasingly used for synthesizing and enhancing medical images, helping address challenges such as limited data, expensive acquisition, and rare disease representation. This systematic review examines studies on generative AI methods for MRI, CT, X-ray, and pathology image synthesis from 2017 to 2026, focusing on synthesis tasks, evaluation strategies, and clinical utility. A PRISMA 2020-compliant search of PubMed, IEEE Xplore, Scopus, and Web of Science identified peer-reviewed research on generative models for medical image synthesis, augmentation, harmonization, or cross-modality translation. Findings show a shift from GAN-based methods to diffusion models post-2022, with MRI and CT studies emphasizing cross-modality translation, and X-ray and pathology studies focusing on augmentation and diagnostic utility. Despite GANs' continued dominance, diffusion models are gaining traction for improving image fidelity and diversity. However, evaluation practices remain inconsistent, with limited inclusion of clinically relevant assessments. This review follows PRISMA 2020 guidelines and provides a narrative synthesis of the evidence.