• There are more than 2,500 public health agencies in the U.S. at the federal, state, local, territorial and tribal levels. This not only leads to great diversity, but as a result public health cannot and does not speak with one voice about interoperability issues (or anything else for that matter). This makes it difficult for some stakeholders to engage public health consistently or to implement solutions that can be used more uniformly and therefore more effectively across public health.
• There is no federal public health law but rather state, local, and tribal law and regulation. The result is that the legal framework is specific to a jurisdiction, and this can inhibit discussion about interoperability as well as implementation. This is best exemplified by our collective inability to reconcile data sharing and consent laws across jurisdictions in the U.S., certainly not for want of trying.
• Most public health activities are federally funded, by CDC, CMS and other federal agencies. Even though the legal framework for public health is state/local/territorial/tribal, there are strong financial incentives for agencies at all levels to comply with the guidelines and requirements that federal funders often stipulate in their grants, contracts and cooperative agreements. While this may sound like a unifying force, it produces tension in some jurisdictions who feel pressure not to comply or results in federal guidelines that still permit a fair amount of variability.
• CDC primarily funds public health program by program, usually due to stipulations from Congress or the reality of federal appropriations. Similarly, state, local, territorial and tribal public health agencies organize their own programs in this “stovepipe” fashion, and the information systems they create are often hostage to the program they support. There are often barriers to creating common, shared or leveraged systems that can be used by multiple programs; those jurisdictions that have been able to implement more integrated systems have usually had to do so with their own funds.
• Technical infrastructure at public health agencies is getting increasingly centralized, especially at the state level. The result is that individual programs are less in control of their system infrastructure and less able to make their own decisions about what systems to deploy and how to deploy them. While the primary motivation for this centralization is cost containment as well as technical risk reduction through more rigorous information security practices, interoperability especially outside of the agency can take on new challenges. In many agencies, for instance, simple installation of a digital certificate may require months of negotiation and delay with internal service providers.

Public health is an active player in health care interoperability with lots of needs and opportunities for internal systems integration as well as external interoperability. The CMS EHR Incentive Programs have pushed many of these activities to the forefront, but many of these clinical reporting requirements were pre-existing and often legally mandated. Service-oriented architecture (SOA) is one approach to making interoperability practical, though given the challenges above, there is a strong role for technical standards in moving public health to greater uniformity. Through increased scalability, lower cost through component re-use, flexibility and greater platform-independence, SOA continues to have increasing use within public health systems and even greater potential for sharing services and capabilities in the larger health care ecosystem.

Additional resources

Arzt, Noam H. with Susan Salkowitz, Evolution of Public Health Information Systems: Enterprise-wide Approaches, July 2007.

Arzt, Noam H., IIS Interoperability Model, June 2008.

Arzt, Noam H., Service-Oriented Architecture in Public Health: Interoperability Case Studies, Journal of Healthcare Information Management, 24(2), Spring 2010.

Arzt, Noam H., The Interoperability of Things, Journal of Healthcare Information Management, 29(4), Fall 2015.