Experience and reflection from China's Xiangya medical big data project.

The construction of medical big data includes several problems that need to be solved, such as integration and data sharing of many heterogeneous information systems, efficient processing and analysis of large-scale medical data with complex structure or low degree of structure, and narrow application range of medical data. Therefore, medical big data construction is not only a simple collection and application of medical data but also a complex systematic project. This paper introduces China's experience in the construction of a regional medical big data ecosystem, including the overall goal of the project; establishment of policies to encourage data sharing; handling the relationship between personal privacy, information security, and information availability; establishing a cooperation mechanism between agencies; designing a polycentric medical data acquisition system; and establishing a large data centre. From the experience gained from one of China's earliest established medical big data projects, we outline the challenges encountered during its development and recommend approaches to overcome these challenges to design medical big data projects in China more rationally. Clear and complete top-level design of a project requires to be planned in advance and considered carefully. It is essential to provide a culture of information sharing and to facilitate the opening of data, and changes in ideas and policies need the guidance of the government. The contradiction between data sharing and data security must be handled carefully, that is not to say data openness could be abandoned. The construction of medical big data involves many institutions, and high-level management and cooperation can significantly improve efficiency and promote innovation. Compared with infrastructure construction, it is more challenging and time-consuming to develop appropriate data standards, data integration tools and data mining tools.

Experiences of building a medical data acquisition system based on two-level modeling.

BACKGROUND AND PURPOSE: Compared to traditional software development strategies, the two-level modeling approach is more flexible and applicable to build an information system in the medical domain. However, the standards of two-level modeling such as openEHR appear complex to medical professionals. This study aims to investigate, implement, and improve the two-level modeling approach, and discusses the experience of building a unified data acquisition system for four affiliated university hospitals based on this approach. METHOD: After the investigation, we simplified the approach of archetype modeling and developed a medical data acquisition system where medical experts can define the metadata for their own specialties by using a visual easy-to-use tool. RESULT: The medical data acquisition system for multiple centers, clinical specialties, and diseases has been developed, and integrates the functions of metadata modeling, form design, and data acquisition. To date, 93,353 data items and 6,017 categories for 285 specific diseases have been created by medical experts, and over 25,000 patients' information has been collected. DISCUSSION AND CONCLUSION: OpenEHR is an advanced two-level modeling method for medical data, but its idea to separate domain knowledge and technical concern is not easy to realize. Moreover, it is difficult to reach an agreement on archetype definition. Therefore, we adopted simpler metadata modeling, and employed What-You-See-Is-What-You-Get (WYSIWYG) tools to further improve the usability of the system. Compared with the archetype definition, our approach lowers the difficulty. Nevertheless, to build such a system, every participant should have some knowledge in both medicine and information technology domains, as these interdisciplinary talents are necessary.