The push to invest more of the healthcare industry’s time and money into promoting good health is, so far, uneven and uncertain in terms of effectiveness. Perhaps nowhere is that more apparent than in federal initiatives to broadly improve health by extending care beyond clinics and pharmacies into neighborhoods and homes.Federal funding for population-health efforts—the management of health and medical care for an entire group of patients or a community—has expanded under the Affordable Care Act. It’s included financing for states and providers to experiment with ways to better coordinate healthcare and other needs that affect health, such as housing and transportation. But the initiatives are not without risk or challenges, a point three federal officials underscored in the latest issue of the New England Journal of Medicine.

Efforts are still underway to identify what works and how to make widespread use of the most effective strategies, write Dr. William Kassler, Naomi Tomoyasu and Dr. Patrick Conway of the agency that oversees Medicare and Medicaid. The CMS Innovation Center, in a report to Congress last month, also said results were largely not yet available for nearly two dozen initiatives to bolster population health, improve quality and increase efficiency in healthcare, financed with $2.6 billion through last year.

Calculating a dividend from those investments presents another challenge, the trio wrote. Kassler is one of the CMS’ chief medical officers; Tomoyasu is deputy director of the prevention and population health care models group within the CMS Innovation Center; and Conway is the CMS’ deputy administrator for innovation and quality.

The return on any investment in prevention will necessarily take time, raising the risk that “current actuarial methods used to evaluate return on investment may underestimate potential savings,” they warned.

Investment at the federal level is not small. Medicare and Medicaid—which combined account for $1 of every $3 the nation spends on healthcare—have increasingly poured money into strategies for disease prevention and health promotion.

Those strategies extend the reach of healthcare beyond hospitals, clinics and pharmacies into neighborhoods, homes and schools. Such extended investment can include help with housing, transportation, literacy, day care and groceries, the officials wrote.

But with that expanded reach comes a debate “regarding the specific population-based activities that fall within healthcare providers’ scope of practice,” wrote the CMS officials. “Because so many factors lie outside clinicians’ control, we need to understand what factors the healthcare system can reasonably be expected to act on, given professionals’ training, infrastructure and scope of practice,” they said. “We also need to determine the appropriate levels of health system accountability for population health outcomes.”

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