Preventive Medicine: A Path to a Healthier Future
Zeba M. Khan, RPh, PhD, Editor-in-Chief, Value & Outcomes Spotlight
For decades, the guiding principle of public health has been a simple, resonant phrase: “An ounce of prevention is worth a pound of cure.” Yet, our modern healthcare systems often operate in reverse. We have built a colossal, technologically advanced, and staggeringly expensive “pound of cure”—a reactive machine designed to treat disease after it manifests. The “ounce of prevention” has remained a noble but chronically underfunded and undervalued afterthought.
The challenge has never been a lack of belief in prevention, but a lack of definitive, large-scale proof of its long-term value. How does the health economics and outcomes research (HEOR) community quantify the economic and health benefits of a heart attack that never happened or a cancer that never developed? The gold standard for medical evidence, the randomized controlled trial (RCT), is often ill-suited for this task. RCTs are expensive, time-consuming, and conducted on narrow, highly controlled patient populations. They are perfect for testing a specific drug’s efficacy, for example, but impractical for measuring the decades-long impact of a lifestyle intervention or a public health policy across a diverse, messy, real-world population.
This is where a paradigm shift, fueled by data, is finally enabling us to demonstrate the real value of prevention. The rise of real-world evidence (RWE)—health information derived from sources outside of typical clinical trials—is providing the longitudinal, large-scale data we have desperately needed. Drawn from electronic health records (EHRs), insurance claims databases, patient registries, and even data from wearable technology, RWE is closing the gap and connecting the dots between laboratory data and real-life health outcomes.
A paradigm shift, fueled by data, is finally enabling us to demonstrate the real value of prevention. The rise of real-world evidence is providing the longitudinal, large-scale data we have desperately needed.
The transformative potential of RWE in preventive medicine is not hypothetical; it’s already in action. Consider the human papillomavirus (HPV) vaccine. While RCTs proved its safety and efficacy in preventing HPV infection, it was RWE that delivered the stunning validation of its public health impact. Large-scale studies using national health registries in countries like Scotland, Sweden, and Australia have demonstrated a dramatic, real-world reduction—up to 100% in some cohorts—in the incidence of precancerous cervical lesions and cervical cancer itself among vaccinated women.1-3 Additionally, the economic argument for prevention is becoming undeniable. Researchers estimate that cervical cancer elimination in Australia will save $45.5 million in treatment and follow-up costs.4 Routine childhood immunizations in the United States between 1994 and 2023 are projected to prevent 508 million cases of illness, 32 million hospitalizations, and 1.13 million deaths, generating direct savings of $540 billion and societal savings of $2.7 trillion. This evidence provides an irrefutable case for vaccination programs, justifying their cost and effort on a global scale.
Similarly, RWE has been instrumental in refining our understanding of chronic disease prevention. Initial trials of statins for preventing cardiovascular events focused on high-risk individuals. However, by analyzing massive EHR and claims databases, researchers could study the effectiveness of statins for primary prevention in a much broader population. This RWE helped inform and validate guidelines recommending statins for individuals with moderate risk, preventing countless cardiovascular events in people who might not have qualified under older, trial-based criteria.
As Jeremy Farrar of the World Health Organization (WHO) emphasizes in our feature article, a shift towards health promotion and disease prevention is crucial to prevent health systems from collapsing under the economic burden of an aging global population and rising chronic conditions. Countries that prioritize prevention, such as the Nordic nations, demonstrate success not by spending more, but by effectively promoting healthy behaviors through public health systems and consistent messaging. The WHO’s “Best Buys” for prevention, if implemented globally, could save 12 million lives, prevent 28 million heart attacks and strokes, and generate over $1 trillion in economic benefits.
The next frontier is even more personal. The proliferation of smartwatches and other wearable devices is generating an unprecedented stream of real-time physiological data. The Apple Heart Study, for example, enrolled over 400,000 participants to use a smartwatch app to screen for atrial fibrillation, a leading cause of stroke. The study demonstrated the feasibility of using consumer technology to identify undiagnosed arrhythmias on a massive scale, opening the door for proactive intervention before a catastrophic event occurs.5 This is prevention on your wrist.
Of course, the path forward is not without its challenges. The quality and interoperability of data sources can be inconsistent. There are significant concerns regarding patient privacy and data security that must be addressed with robust governance. Furthermore, drawing accurate causal inferences from observational or patient-reported data requires sophisticated analytical methods to minimize bias.
In countries like the United States, where universal healthcare is not a given, unique challenges exist, such as many young adults lacking regular healthcare providers and insurance for preventive screenings. Strategies like value-based care models, incentives for healthy lifestyles, and ensuring that no-cost preventive services (like those mandated by the Affordable Care Act) are widely utilized and are understood to be critical.
However, these are not insurmountable obstacles; they are opportunities for innovation and investment. We need to build a robust data infrastructure, standardize data collection, and develop transparent, powerful analytical tools. Policy makers, payers, and other key stakeholders must evolve, creating frameworks that accept RWE as valid for evaluating the cost-effectiveness of preventive measures. If analysis of RWE indicates a digital wellness program significantly reduces the incidence of type 2 diabetes in a large, diverse population, it should be reimbursed as readily as the medications used to treat the disease.
For too long, our healthcare system has been locked in a costly cycle of reaction. By embracing RWE, we can finally provide the proof needed to shift our focus and resources toward proactive, preventive care. This data-driven revolution is our best hope for building a healthier, more equitable, and more sustainable future—one where we finally value the ounce of prevention, because we now have the data to prove it’s worth a ton of cure.
As always, I welcome input from our readers. Please feel free to email me at zeba.m.khan@hotmail.com.
References
- Palmer T, Wallace L, Pollock KG, et al. Prevalence of cervical disease at age 20 after routine vaccination with bivalent HPV vaccine at age 12-13 in Scotland: retrospective population study. BMJ. 2019;365:l1161. doi: 10.1136/bmj.l1161
- Lei J, Ploner A, Elfstrom KM, et al. HPV vaccination and the risk of invasive cervical cancer. New Engl J Med. 2020;383(14):1340-1348. doi: 10.1056/NEJMoa191733
- Smith M, Brotherton J, Machalek D, et al. 2025 Cervical Cancer Elimination Progress Report: Australia’s progress towards the elimination of cervical cancer as a public health problem. https://www.report.cervicalcancercontrol.org.au Published online November 17, 2025. Accessed January 29, 2026.
- Lew J-B, Howard K, Gertig D, et al. Expenditure and resource utilisation for cervical screening in Australia. BMC Health Serv Res. 2012;12:446. doi: 10.1186/1472-6963-12-446
- Perez MV, Mahaffey KW, Hedlin H, et al. (2019). Large-scale assessment of a smartwatch to identify atrial fibrillation. New Engl J Med.:2019;381(20):1909-1917.
