Centering proportionality in public health thinking

On doing the most possible good while doing the least possible harm.

There is an old saying from the world of competitive fencing, one that is used to teach beginners how to hold the foil—a light, flexible blade used in the sport. The saying is, “Hold it like you would a bird. Too tight and you choke it. Too loose and you let it fly away.” That is proportionality. The pressure applied to the foil must be in proportion to how much is necessary for maintaining control. Too firm a grasp prevents the fencer from wielding the foil nimbly. Too loose a grasp and an opponent can easily knock it to the floor. Success lies in applying the right proportion of strength—no more, no less.

The principle of proportionality wends its way through several disciplines. In mathematics, proportionality refers to a correspondence of ratios. In law, it can refer to the principle that “the punishment should fit the crime.” It can also play a role in international law concerning the use of force in an armed conflict, drawing a distinction between the use of force as a proportional response to a provocation and force that is disproportionate and therefore beyond the bounds of sanctioned conflict. In the context of medical ethics, proportionality helps shape decisions about the cost and benefits of various interventions. Perhaps, for example, a drug may cure a disease, but with the certainty of painful side effects. Is the treatment, then, proportional to the illness? 

In public health, we, too, can find ourselves in positions where proportionality is of core importance. Public health often makes recommendations to policymakers which involve “asks” of the public. We propose actions that entail some restraint or sacrifice in exchange for less risk of harm. We saw this during the pandemic, when public health played a role in the adoption of lockdowns, mask mandates, and vaccination requirements. This recent history reflects a dynamic that has long characterized what we do. As long as public health has existed, it has at times placed checks on individual autonomy in the name of the greater good of supporting a healthier society. From quarantines during times of plague to mandatory treatment for diseases like tuberculosis to taxes on harmful products like sugar-sweetened beverages, public health has supported measures which place impositions on the public. In some cases, such as the extended restrictions on movement of the COVID-19 moment, these impositions created their own challenges for health. This places public health, a field which exists to shape healthier populations, in the difficult position of sometimes proposing measures which create tradeoffs for health. We may do a little harm here to prevent greater harm there, responding to the data and the reality of evolving challenges. In this way, we find ourselves much like the fencer trying to properly hold their foil. In order to be effective in our core mission, we, at times, impose restrictions on populations which, if too tight, could cause undue harm, but, if too loose, could mean opening the door to greater harm. Proportionality helps us to strike this balance, to advocate for policies that suit the moment, imposing on the public no more than is necessary to support health.

It can be uncomfortable for us to acknowledge the need for proportionality in our work. We tend to prefer the thought that the steps for which we advocate are entirely on the side of better health for all, with little downside in terms of unintended or overlooked consequences. Seeing our work through the lens of proportionality means acknowledging that there are indeed ways our efforts can create challenges for health. Given that the work of public health will always involve such tradeoffs, we have a responsibility to think about the role of proportionality in our work.

It strikes me that proportionality in public health is fundamentally about the question: what is the potential for harm and what is the potential for good in a public health action? As we navigate this philosophical space, the following three principles can, I think, serve as useful guides, helping us to better engage with proportionality in this post-war moment.

First, proportionality has to be central to public health. Throughout the history of public health, we have, at various points, chosen to embrace certain concepts as core to our field. For example, as we became more focused on crafting polices that shape health at the population level, we began to have more conversations about advancing these polices while respecting individual autonomy. As it became clear that social exclusion and historical injustice are foundational drivers of poor health, we embraced the pursuit of equity as a foundational focus. Now, in this post-COVID moment, public health has, in many ways, more power than ever before to shape policy and engage with the public debate to advance our favored solutions. With this newfound power comes the responsibility to place proportionality at the center of public health thought and action. We should never find ourselves in the position of recommending an action that might cause more harm than it prevents. This means having a clear-eyed view of the potential harms of any step we are considering. We need to engage dispassionately with the data to see both the costs and benefits of a given action. In doing so, we should bear in mind that these harms do not always happen immediately, nor are they always easy to see. They can occur slowly over the long-term, as in the case of the burden of mental illness during and after COVID-19, or in the potential lifelong harms caused by educational disruption over the last few years. This urges a foundational focus on proportionality as a means of ensuring our actions do not result in undue harm either in the present or in the future.

Second, it is important that our focus on proportionality is informed, always, by our pursuit of equity. In thinking about equity in the context of proportionality, I am reminded of this passage from the Public Health Code of Ethics:

“Public health practitioners and organizations have an ethical obligation to use their knowledge, skills, experience, and influence to promote equitable distribution of burdens, benefits, and opportunities for health, regardless of an individual’s or a group’s relative position in social hierarchies. Health justice and equity also extend to ensuring that public health activities do not exacerbate health inequities.”

Just as public health is centrally concerned with ensuring that all have access to the resources and opportunities that support health, it has a responsibility to ensure that no groups bear undue burdens. This means that our calculus when it comes to the harm our interventions may cause must account for the disproportionate burden of poor health experienced by certain marginalized groups. This can help us avoid taking actions that may worsen inequities even as they might benefit the overall population. It is not enough for a given measure to be worth the inconvenience or harm it may cause the population at large. We must also consider how it may affect groups whose health is poorer than the average, or for whom the burden of our intervention will be particularly heavy.

We may think, for example, that lockdowns are worth it, in the short-term at least, because the harms they can create—the mental health burden of isolation, the economic effects of closing businesses, educational disruptions—seem justified in the face of a novel pathogen that has become a global pandemic. But what about the populations that cannot easily work remotely? What about the delivery truck drivers, retail workers, Uber employees—all those whose jobs put them into direct contact with the public? These questions become even more urgent when we consider that many of these workers are people of color who already suffer from a range of health inequities driven by underlying causes that have historically shaped these gaps. Measures which may be proportionate in the context of the overall population may not be proportionate when we consider how they might affect vulnerable groups. We also need to be honest with ourselves about just who benefits from a given public health measure. When we talk about mandatory COVID-19 vaccination for children, for example, are we doing so because we think it will benefit a population at relatively low risk or because, really, we think it will make us, older adults, safer? Such honesty can help maintain the proportionality of our efforts and stop us from exacerbating inequities, or from creating new ones, in our pursuit of health.

Third, it is important to remember that our conception of harm is shaped by what we value. Proportion depends on being able to weigh the risks and benefits of a given measure, but, as I have recently written, risk is not a value-neutral concept. It is influenced by our biases, by the individual and cultural lens through which we view the world. This has implications for how we determine whether a policy or action is truly proportional. Consider the example of alcohol consumption. It is, I think, fair to say that many in public health regard alcohol consumption as nothing more than a health hazard. For this reason, we may not regard efforts to ban or severely limit the sale of alcoholic beverages as anything less than an unalloyed good. We might therefore favor, of all possible actions to address the health harms of drinking alcohol, the strictest possible ban on the practice. But for many, consuming alcohol is a source of pleasure, and an activity tempered by moderation. This reality should change our understanding of proportion as we consider alcohol policy. Even if it does not change our position on alcohol, it should help us to think about how different populations have different definitions of harm and how it is important for public health to take these perspectives into account. And that should guide how we approach efforts to limit alcohol consumption, through changing what does give pleasure in the direction of more healthful pastimes, rather than simply imposing a ban heedless of how weighty it may feel for some.

Another area where differing definitions of harm have created challenges for public health is in our engagement with gun violence. We know the data that say guns are a clear threat to health. The regularity with which we see gun violence and mass shootings—like the recent tragedy in Nashville—gives added impetus for us to push for measures that drastically curtail the power of guns to cause harm. From our perspective, there is little downside to such measures, so steps like a national gun ban might seem proportional to the threat of gun violence in the US. I have often argued for measures which would help get us closer to a world without guns, and I continue to believe the problem of gun violence remains vastly disproportionate to the legislative steps we have taken to address the crisis. Nevertheless, it is important to remember—and I say this to myself as much as I write for anyone else—that, for many, guns matter as a source of cultural pride and as a practical means of hunting and self-defense. While this should not necessarily change our advocacy of the policies that address gun violence, it should factor into our sense of proportionality with respect to this issue, if only to help us develop a fuller picture of the cultural and political forces at play. We may think we are working to advance measures that are proportional to a public health threat, but, in the case of guns, many regard what we see as commonsense solutions as disproportionate to the challenge at hand. Understanding this could help us to find areas of common ground, to advance solutions within the space of political practicality. It can also serve as a reminder that our thinking about proportionality should always be informed by the awareness that we are treading in a value-laden area.

I have been writing this set of essays in 2023 to the end of articulating a practical philosophy of health in what I have called a post-war period. This leads me to focusing on principles that allow us to maximize our capacity to support health while minimizing the harms our efforts may cause. Choosing to prioritize proportionality as central to our thinking can help us to do so. It can ensure we act, always, within the bounds of what is necessary to create better health for all, imposing on the public just as much as we need to, but never more than we must.

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Also this week.

New in JAMA Health Forum, thoughts with Salma Abdalla on the reasons for optimism that we can build a healthier world, one informed by the ongoing lessons of COVID-19 and founded on a vision of the common good.