Auditing the Human BioMolecular Atlas Program (HuBMAP) Human Reference Atlas (HRA): An Evaluation of Core Digital Objects

Data auditing has become increasingly critical for large-scale biomedical repositories as they serve diverse research communities while maintaining scientific rigor and compliance with established standards. The Human BioMolecular Atlas Program (HuBMAP) aims to map the human body at single-cell resolution through curated spatial and molecular data. The Human Reference Atlas (HRA), a central output of HuBMAP, includes datasets such as Anatomical Structures, Cell Types and Biomarkers (ASCT+B) tables, 2D Functional Tissue Unit (FTU) illustrations, 3D reference organ models, and Organ Mapping Antibody Panels (OMAPs). This study reports the first comprehensive, third-party audit of the HRA, conducted from March 2024 to August 2025 to assess data quality, internal consistency, and adherence to Standard Operating Procedures (SOPs). The audit methodology combined systematic evaluation of metadata completeness and correctness with visual inspection protocols designed to assess user experience and functional utility across different digital object types. Using a combination of visual inspections, file metadata analyses, and spreadsheet comparisons across 34 ASCT+B tables, 22 2D FTU illustrations, 30 3D reference models, and 21 OMAP datasets, the audit demonstrated overwhelmingly positive results, with compliance rates of 74-100% across evaluation criteria, and most criteria exceeding 90%. Findings indicate that HuBMAP maintains robust curation standards, with structural issues present in fewer than 10% of ASCT+B tables. This audit provides a replicable model for future quality assurance activities in large-scale biomedical data infrastructures and highlights the importance of continuous audit processes for ensuring data integrity, transparency, and usability in contemporary digital curation contexts.