Applying a Population Lens to Population Health

The public health field focuses on population health, but it can be challenging to summarize the health of an entire national population: populations, after all, are composed of myriad subpopulations, each with its own health profile. Improving population health requires having clear goals and robust data collection, coupled with a coordinated set of policies and programs, multisector collaboration, and adequate resources. Although there is no single measure of population health, life expectancy and mortality rates are commonly used to characterize and compare populations. The Department of Health and Human Services defines a broad set of population health goals, the Healthy People goals, each decade.

A key subpopulation that must be considered in efforts to enhance population health is children, a group whose characteristics pose distinct opportunities and challenges (see table). The developmental and physical changes that occur between birth and young adulthood underscore children’s particular vulnerabilities as they age, grow, and ultimately transition from dependence to independence, when they’re expected to have acquired the skills to become productive members of society. Child health is influenced by various medical and nonmedical factors. Most children in the United States are healthy, and overall mortality is low. Whereas child mortality has limited applicability as a summary health measure, the first year of life is a period of elevated risk, and infant mortality is commonly used as a measure of population health. The favorable health profile of U.S. children leads to strong performance in international rankings, but the preponderance of healthy children may keep us from recognizing subgroups with higher-than-average morbidity and mortality, including poor children. Despite recent improvements in children’s socioeconomic status, 14% of American children live in poverty, as compared with about 9% of adults.1 It’s discouraging that the greatest reductions in state funding for public health between 2008 and 2018 were in the areas of child, maternal, and family health.2

An example of the value of applying a subpopulation lens to a public health issue comes from 2018, when many immigrant families who crossed the U.S. southern border were split up. This policy was intended to discourage unauthorized immigration, particularly among adults, but a large number of children were affected. These children were separated from their parents and placed in large-scale custodial arrangements. Pediatricians were immediately concerned about the health, developmental, and emotional consequences of the family-separation policy. Infectious diseases were an important risk, as was the likelihood of emotional distress and developmental regression in a setting that lacked familiar, consistent caregivers and a comforting daily routine. During a developmental phase in which children rely on family members to meet their basic needs and provide emotional stability to promote health, immigrant children were at risk for isolation, uncertainty, and illness.

The American Academy of Pediatrics defines the scope of pediatrics as including “physical, mental, and social health,” in recognition of the complex, dynamic interplay between physical and nonphysical aspects of health. Pediatricians emphasize prevention, early identification, and management of health issues, including infectious diseases, dental caries, asthma, obesity, chronic illnesses, and mental health problems. The emphasis on prevention in pediatric practice contrasts with adult medicine, which