Imagine a busy night in a local emergency department. The waiting room is full of patients, and everyone is working to make sure every patient is seen. But in the back of their mind, they are listening for a sound that’s become all too familiar — an overhead notification that another victim of gun violence will need life-saving care.

Everyone runs to the trauma bay, ready to give it their all. Sometimes those efforts are successful. Sometimes they are not. But each time, the trauma that violence inflicts — on the patient, the family, the community, and the care team — lingers long after the trauma bay is silent.

As a pediatrician, I find these calls to be devastating. And many times, my colleagues have reached out to me with one question: What can we do to prevent this? Tired of treating patients after the shots are fired, they long to be part of a solution that begins much further upstream.

This is where a public health approach begins. With a focus on prevention, in addition to treatment. The basic tenets of a public health approach are defining the problem, identifying the risk and protective factors, developing and testing prevention strategies, and making sure those strategies are adopted and scaled to effect. But what does this look like, practically?

Gun violence is a public health problem because it causes injury and death. It significantly disrupts the physical and emotional well-being of those involved. It may seem obvious that defining the problem is a necessary first step, but in truth, it is a challenging one. We need to understand who violence touches (and just as important, who it doesn’t touch and why), where it’s happening and what is notable about those locations, when violence occurs, and how it is usually enacted.

This requires using all the data available to us, often from many different sectors, to really drill down on the micro-environments where violence is able to thrive, in order to transform those environments. The focus has to be the population of those exposed to the problem — not just individuals.

A careful and thoughtful determination of the risk and protective factors that influence violence will inform where prevention will most likely be effective. A thorough understanding of risk needs to take a broad range of factors into effect. In addition to naming the racial and ethnic disparities that define firearm violence, we have to name the key drivers.

For example, there is a growing recognition of the role of trauma healing, as trauma both results from violence and is a risk factor for exposure to violence. Unemployment and high levels of gun violence occur in similar parts of the city. Racism, a public health crisis, is another major driver of these trends. And we must acknowledge that we need to engage those closest to the problem. All the data we have are without context if we don’t commit to authentic community engagement.

We are often hesitant to embrace community transformation as a way to address gun violence. We are concerned that transformation takes too long — we need to save lives today. This hesitancy is understandable, because this problem could not be more urgent, but we must not fail to recognize the body of evidence that demonstrates that providing employment opportunity and trauma healing, transforming the built environment, and improving the expectations of youth about their future — all transformative, asset-based approaches — are showing promise in reducing violence.

These are strategies that address risk factors and build upon protective factors. And their effect is seen not just in a generation, but sometimes within a few years of implementation. From the policies we enact at the federal, state, and local level, to the way we educate our youth, to how we beautify our city, to how we enforce the law — all sectors play a critical role.

Mitigating risk factors by focusing on the environment means engaging honestly with why there are so many guns on the street, and how society needs to change the way guns are distributed. State and federal inaction on this topic over decades has been a critical missed opportunity in primary prevention. Guns make altercations significantly more lethal, and their presence in highly traumatized environments is a risk factor that must be addressed.

Ensuring widespread adoption is a necessary final step in any public health endeavor. Many promising programs begin as regional interventions, focused in a single neighborhood or hospital system. But once effectiveness is demonstrated, programs that work need to be made available to vulnerable populations throughout the city and sustained through each phase, from initial implementation to maintenance. As programs expand, ongoing evaluation ensures that they maintain their effectiveness and informs necessary changes and modifications.

How is our city directing its focus on a public health approach to violence? We are drilling down on what we know about this problem, with precision — the who, what, where, when, and why. We are working to identify risk and protective factors so we know where to concentrate our energy and resources. We are inviting our community members to inform our understanding of these factors, and humbly acknowledging that we don’t know what we don’t know.

We are working to design and expand interventions that build on protective factors and mitigate, or eliminate, risk factors. We are also working to evaluate these interventions with vigor, so we understand what’s working, and why. And finally, when we find something that works, we must commit to it for the long haul — until we turn the tide once and for all.

Ruth Abaya is the injury prevention program manager for the Philadelphia Department of Public Health. She is also an emergency medicine pediatrician at CHOP, a clinical scholar of the CHOP Violence Prevention Initiative, and a Stoneleigh fellow.