Milliman’s Data Coup: Cracking Japan’s New Healthcare Data Frontier

TOKYO, JAPAN – August 10, 2026 – In a move that signals a seismic shift in Japan’s healthcare data landscape, global actuarial firm Milliman, Inc. has secured a coveted certification to operate within a new, powerful data framework. The firm announced it is now a "Certified Pseudonymized Medical Information User," a designation granted under Japan's recently amended "Next Generation Medical Infrastructure Act" (NGMIL). While the announcement may seem like procedural minutiae, it represents a significant strategic victory, placing Milliman at the heart of a national effort to revolutionize medical research and development.

This certification is more than a license; it's a key to a new class of data that was previously inaccessible for large-scale private research. By becoming only the second private company to gain this status, Milliman is positioning itself as a critical enabler in a market wrestling with data fragmentation and privacy, yet hungry for the innovation that real-world evidence can unlock. The move underscores a broader trend where deep analytical expertise, not just technological prowess, is becoming the primary currency in the future of healthcare.

The New Frontier: From Anonymized to Pseudonymized

At the core of this development is Japan's ambitious NGMIL, which saw a pivotal amendment come into force in April 2024. The legislation’s goal is to balance the immense potential of big data in medicine with stringent privacy protections. For years, researchers have been limited to using "anonymized" medical information—data stripped of identifiers to a degree that makes re-identification impossible. While safe, this process often sacrifices crucial details, rendering the data less effective for complex analysis. Key test values might be generalized, rare disease codes removed, and the ability to track a single patient’s journey over time—a cornerstone of longitudinal research—is lost.

The 2024 amendment introduced a powerful alternative: "pseudonymized medical information." This new data class represents a carefully calibrated middle ground. Direct identifiers like names are replaced with a non-identifiable key, or pseudonym. While the data cannot be traced back to an individual without a separate, securely held key, it retains its original granularity. This seemingly subtle distinction is a game-changer. Researchers can now analyze specific, unaltered test results and track patient outcomes across different treatments and time periods. For fields like rare disease research, where every data point is precious, or in evaluating the long-term cost-effectiveness of a new drug, this level of detail is transformative.

The Japanese government’s strategy is clear: rather than allowing open access, it has created a rigorous certification system for trusted entities to handle this sensitive data within secure environments. This framework is designed to accelerate R&D for pharmaceuticals and medical devices while assuring the public that their information is being used responsibly.

Milliman's Strategic Play for a Data-Driven Edge

Milliman's achievement of Type II certification places it in an elite group. The firm follows pharmaceutical giant AstraZeneca, which received its own certification earlier, confirming that Japan is selectively opening its data ecosystem to players with demonstrable expertise and robust governance. For an actuarial consulting firm, whose entire business is built on data science, risk modeling, and predictive analysis, this move is a masterstroke. It leverages the company’s core competencies and applies them to one of the most valuable and complex datasets in the world.

"With the acquisition of Type II certification... we have established a framework to utilize real-world data in a safer and more advanced manner," said Kosuke Iwasaki, Leader of Milliman’s healthcare Practice in Tokyo. His statement highlights the dual focus on security and advanced analytics. The firm is not just accessing data; it is positioning itself as a trusted interpreter and value assessor.

This certification provides a profound competitive advantage. While other consulting firms may offer strategic advice, Milliman can now back its recommendations with analyses derived from a data source its competitors cannot access. The firm plans to support a diverse clientele, from pharmaceutical companies seeking to prove the value of new therapies to government bodies designing more efficient healthcare policies. As Iwasaki noted, this will enable solutions like "visualizing disease burden, evaluating the value of early diagnosis and treatment, analyzing healthcare cost optimization, and designing outcome-based policies." This is the bread and butter of actuarial science, now supercharged with an unparalleled data source.

Unlocking Real-World Evidence Amidst Systemic Challenges

Milliman’s new capability arrives at a critical moment for Japanese healthcare. For decades, the system has been hampered by significant data challenges. Despite the existence of the massive National Database of Health Insurance Claims (NDB), its data has been fragmented and difficult to use for comprehensive research. The lack of patient outcome data linked to claims, for example, has been a major barrier to generating meaningful Real-World Evidence (RWE)—insights into how treatments perform in everyday clinical practice, outside the controlled environment of a clinical trial.

The NGMIL’s new framework directly confronts this issue by enabling the consolidated analysis of pseudonymized data, potentially linking it with public databases like the NDB. This creates the possibility of building a holistic, longitudinal view of patient health across the nation. Milliman, as a certified user, is now one of the key architects of this new RWE infrastructure.

The impact will be felt most acutely in areas that have been stymied by data limitations. Pharmaceutical companies can build stronger cases for regulatory approval and reimbursement by demonstrating a drug's efficacy and safety in the real world. Health economists can conduct more precise cost-effectiveness studies, helping to ensure the sustainability of Japan’s healthcare system as its population ages. And for patients with rare diseases, the ability to analyze granular, unaltered medical records across a large population offers new hope for understanding disease progression and developing targeted therapies.

The Broader Implications for a Digitalizing Healthcare System

This development is not happening in a vacuum. It is part of a sweeping digital transformation across Japan’s medical landscape, supported by initiatives like the AI Promotion Act and amendments to the Digital Administration Act. The government is actively encouraging the use of advanced technology, from electronic medical records to AI-driven diagnostics, to build a more efficient and effective healthcare system.

In this context, certified data users like Milliman and AstraZeneca become more than just service providers; they are foundational pillars of this new ecosystem. They provide the analytical engine that turns raw data into actionable intelligence, fueling innovation for both private industry and public policy. Their work will help validate new digital health tools, optimize clinical pathways, and ultimately contribute to the national goal of extending healthy life expectancy.

By entrusting this powerful data to a select group of certified entities, Japan is betting that rigorous governance can coexist with rapid innovation. Milliman’s certification is a testament to this new model, where deep analytical expertise and a commitment to security are the price of admission to the next generation of medical research. As the firm begins to leverage this unique advantage, its work will not only shape the strategies of its clients but also help define the future of Japan's data-driven healthcare system.