Sato Jumpei, Mitsutake Naohiro, Yamada Hiroyuki, Kitsuregawa Masaru, Goda Kazuo
Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo, Japan.
Institute for Health Economics and Policy, Minato-ku, Tokyo, Japan.
Heliyon. 2023 May 12;9(5):e16209. doi: 10.1016/j.heliyon.2023.e16209. eCollection 2023 May.
Japan's national-level healthcare insurance claims database (NDB) is a collective database that contains the entire information on healthcare services being provided to all citizens. However, existing anonymized identifiers (ID1 and ID2) have a poor capability of tracing patients' claims in the database, hindering longitudinal analyses. This study presents a virtual patient identifier (vPID), which we have developed on top of these existing identifiers, to improve the patient traceability.
vPID is a new composite identifier that intensively consolidates ID1 and ID2 co-occurring in an identical claim to allow to collect claims of each patient even though its ID1 or ID2 may change due to life events or clerical errors. We conducted a verification test with prefecture-level datasets of healthcare insurance claims and enrollee history records, which allowed us to compare vPID with the ground truth, in terms of an identifiability score (indicating a capability of distinguishing a patient's claims from another patient's claims) and a traceability score (indicating a capability of collecting claims of an identical patient).
The verification test has clarified that vPID offers significantly higher traceability scores (0.994, Mie; 0.997, Gifu) than ID1 (0.863, Mie; 0.884, Gifu) and ID2 (0.602, Mie; 0.839, Gifu), and comparable (0.996, Mie) and lower (0.979, Gifu) identifiability scores.
vPID is seemingly useful for a wide spectrum of analytic studies unless they focus on sensitive cases to the design limitation of vPID, such as patients experiencing marriage and job change, simultaneously, and same-sex twin children.
vPID successfully improves patient traceability, providing an opportunity for longitudinal analyses that used to be practically impossible for NDB. Further exploration is also necessary, in particular, for mitigating identification errors.
日本国家级医疗保险理赔数据库（NDB）是一个汇总数据库，包含了向所有公民提供的医疗服务的全部信息。然而，现有的匿名标识符（ID1和ID2）在数据库中追踪患者理赔记录的能力较差，阻碍了纵向分析。本研究提出了一种虚拟患者标识符（vPID），它是在这些现有标识符的基础上开发的，以提高患者可追溯性。
vPID是一种新的复合标识符，它集中整合了在同一理赔记录中同时出现的ID1和ID2，即使其ID1或ID2可能因生活事件或文书错误而改变，也能收集每个患者的理赔记录。我们使用医疗保险理赔和参保人历史记录的县级数据集进行了验证测试，这使我们能够在可识别性得分（表明区分一个患者与另一个患者理赔记录的能力）和可追溯性得分（表明收集同一患者理赔记录的能力）方面将vPID与真实情况进行比较。
验证测试表明，vPID的可追溯性得分（三重县为0.994；岐阜县为0.997）显著高于ID1（三重县为0.863；岐阜县为0.884）和ID2（三重县为0.602；岐阜县为0.839），可识别性得分与之相当（三重县为0.996）且更低（岐阜县为0.979）。
vPID似乎对广泛的分析研究有用，除非研究关注vPID设计局限性的敏感案例，如同时经历婚姻和工作变动的患者以及同性双胞胎子女。
vPID成功提高了患者可追溯性，为NDB过去实际上无法进行的纵向分析提供了机会。还需要进一步探索，特别是为了减少识别错误。
