The integration of artificial intelligence (AI) into healthcare has enhanced data-driven decision-making, but missing data remains a major barrier to reliable model performance. This narrative review synthesizes literature on missing data in clinical machine learning, focusing on modeling decisions, common pitfalls, and emerging reporting standards within AI-enabled healthcare systems.Missing data in healthcare arises from sources such as electronic health records (EHRs), wearable devices, and clinical trials, and may follow mechanisms including missing completely at random (MCAR), missing at random (MAR), or missing not at random (MNAR). Addressing these gaps requires appropriate imputation strategies, from statistical methods like multiple imputation to advanced deep learning approaches such as generative adversarial networks (GANs), each carrying implications for bias and model generalizability.This review highlights key challenges, including underreporting of missingness, insufficient sensitivity analyses, and neglect of imputation uncertainty. It also examines evolving reporting standards that emphasize transparency in missing data handling. By synthesizing cross-study evidence, the review proposes a systems-level framework for integrating missing data management into AI governance, supporting more reliable, transparent, and equitable healthcare analytics.