Last year, I spoke with a researcher who had spent three years trying to answer what seemed like a straightforward question: Do patients with diabetes receive better care when their doctors can access their full medical history across different health systems? She had the methodology in place, a potential funder identified, and a clear sense of how the findings could improve outcomes for millions of Americans. What she did not have was access to the data needed to answer her question.
Her experience is not unique. I have watched promising studies stall, not because the science was weak, but because the information needed to test good ideas was scattered across organizational silos, trapped in incompatible systems, or governed by rules that were difficult to navigate even for experienced researchers.
This gap between questions and answers is more than an academic frustration. It is a real barrier to improving care. When researchers cannot access the data needed to understand what works, patients live with the consequences of that uncertainty.
That challenge helps explain why the Health Data for Action (HD4A) program took a different approach. Rather than treating data access as a downstream problem for individual investigators to solve, HD4A focused on building partnerships that connected researchers with real-world data from health systems, payers, and states, supported by clear governance and shared expectations for use. The program demonstrated that access is not simply about making data available but creating conditions that allow data to be used responsibly and effectively.
What became possible through this approach is instructive. Through HD4A, researchers were able to work with large, longitudinal data sources such as state all-payer claims databases, enabling analyses across payers and over time that would have been difficult to achieve otherwise. Others gained access to electronic health record data that linked clinical information with social context, making it possible to examine how care varies across populations and settings.
These examples matter, but not because they are unique to HD4A. They matter because they show what changes when access is treated as infrastructure rather than an afterthought. In each case, progress depended less on the novelty of the dataset and more on the partnerships behind it. Data holders, researchers, and intermediaries worked together to establish governance, documentation, and trust, ensuring that data were usable for serious analysis while protecting patient privacy and organizational interests.
That lesson is especially relevant as the health data environment grows more complex. Health systems and payers face legitimate concerns about privacy, competition, and regulatory risk. At the same time, policymakers and communities increasingly expect decisions to be grounded in evidence drawn from real-world experience. These tensions cannot be resolved through mandates alone. They require durable frameworks that balance access with accountability and that can withstand political and technological change.
HD4A offers a glimpse of what those frameworks can look like, but the work cannot stop with a single program. Improving data accessibility in the years ahead will require sustained investment in governance models, incentives for participation by data holders, and technical standards that support research and learning, not just billing or compliance. It will also require continued attention to trust, both among institutions and with the public whose data make this work possible.
The stakes are high. Every delay in answering questions about effective care, equitable access, or efficient delivery has real consequences for patients. The researcher I mentioned earlier eventually found a way to move forward with more limited data, but her conclusions were necessarily constrained. How many insights about better care never surface because the right connections are not in place?
As health care and health policy challenges become more urgent, strengthening data partnerships is not optional. It is foundational. Programs like HD4A remind us that the quality of our evidence depends on the quality of our connections, and that investing in access is one of the most practical steps we can take toward better decisions and better health.