The Trust for America’s Health latest annual report on U.S. public health expenditures was released last week, reminding us that good data on this topic are so frustratingly elusive. Consistent with past years, the report concludes that the U.S. public health system is “chronically underfunded.” But the sad fact is that available data are woefully inadequate to support this conclusion with any reasonable level of confidence and empirical precision.

As noted in previous posts, a high degree of uncertainty surrounds our best estimates of governmental public health spending. Three basic questions of public finance go mostly unaddressed in public health:

1. How much does the nation currently spend on public health activities?

2. Who pays for these activities?

3. How are funds allocated and used across programs and population groups?

Without solid answers to these questions, it is impossible to make a strong case that public health is “underfunded” in the sense that current spending falls below a given threshold defined by objective measures of need, risk, or efficiency. Moreover, answering the basic public finance questions are necessary prerequisites for determining the health and economic value of investments in public health strategies. TFAH deserves credit for soldiering through this data desert, scraping information from public budget documents, websites, and interviews with public health officials. But these sources cannot yield the completeness, comparability and granularity of data needed for sound policy analysis and deliberation, much less for credible economic research and evaluation.

What makes this fiscal opacity even more frustrating is that mechanisms currently exist that could be employed to generate high-quality data on governmental public health spending: the U.S. Census Bureau’s annual Survey of Government Finances and the quinquennial Census of Governments. These mechanisms could be used to produce government-wide data on how much is spent on public health activities, who pays, and how funds are used. These mechanisms could be used to capture and analyze data on the incidence and level of spending in high-priority areas like tobacco prevention, obesity prevention, infectious disease control and food safety protection – information that could be combined with existing disease and risk surveillance data to help society make better decisions about where and how to deploy resources, and to help us learn faster what’s working and what’s not.

Of central importance, such data would fill in the many unknowns inherent in existing financial data captured from periodic surveys of state and local public health agencies, which are subject to the vagaries of how public health responsibilities are divvied up within state and local government bureaucracies, and how these bureaucracies keep their books. (Although their financial measures are imperfect, these periodic surveys are extremely valuable for conducting research on the implementation and impact of public health strategies, as my own studies and many others in the field of PHSSR illustrate).

Why aren’t public health expenditure data already regularly produced? Using the federal government’s existing governmental data collection mechanisms to produce better data on public health spending would probably require channeling some additional funding to the Census Bureau – a nontrivial but not insurmountable requirement. The larger challenge involves reaching consensus on what set of governmental activities should be defined and measured as public health responsibilities on a nationwide basis. This is a long-standing problem for the public health profession, which often relies on flexible and fuzzy conceptualizations of public health activity to build broad advocacy coalitions and to navigate ideological differences of opinion about the appropriate roles of government in the health policy arena. To counter this problem, a 2012 report by the Institute of Medicine recommended a national consensus process to identify a “minimum package” of public health services that should be available in all states and communities, and some work is now underway.

Many other social sectors benefit from regular flows of reliable financial data, including education, housing, criminal justice, and medical care. These data enhance research and evaluation, policy analysis and decision-making, managerial benchmarking and quality improvement, and governmental accountability and transparency. Maybe it is time to generate and use such data for public health.