When Secondary Prevention is Harmful

The current philosophy in our healthcare system maintains that the best way to keep people healthy is to constantly check if they have signs or symptoms of disease. But how much sense does this credo actually make?

Over the past few decades, the American healthcare system has become principally focused on secondary prevention — that is, detecting illness and disease at early stages in order to reduce potential negative health outcomes. Yet many studies have shown that primary prevention methods which aim to prevent the onset of disease, such as diet and exercise, are much more effective and cost efficient. In fact, there is some evidence that in addition to costing more time and money for patients and hospitals, excessive screening may actually lead to heightened anxiety and increased exposure to radiation — both of which cause certain diseases.

G. Welch, a professor of medicine at the Dartmouth Institute for Health Policy and Clinical Practice, points out that the National Cancer Institute’s recent studies of prostate and ovarian cancer screenings indicate that these procedures rarely save lives. Some meta-analyses indicate that certain processes, such as breast cancer screening, may reduce mortality by up to 20%, but other studies suggest that the life extension offered by screenings may only be a few minutes. Additionally, the cost of false-positives can be enormous: procedures are expensive, can be painful and psychologically traumatizing, and many, such as chemotherapy, are themselves carcinogenic.

The costs of false-positives can be enormous: procedures are expensive, can be painful and psychologically traumatizing, and many, such as chemotherapy, are themselves carcinogenic.

It is for this reason that Welch asserts that the process of screening doesn’t actually promote health at all. “People suffer from more anxiety about their health, from drug side effects, from complications of surgery. A few die. And remember: these people felt fine when they entered the healthcare system.”

So why do we still focus on screening rather than both prevention and intervention?

Warshaw-xray street artHuman beings tend towards loss aversion, focusing more on ways to avoid losses than acquiring gains (a theory outlined by Daniel Kahneman of Princeton University). In the case of primary versus secondary prevention, this frequently translates to advocating for screening despite its low margins of success, due to the fact that the consequences of not getting screened could be fatal. Kahneman’s theory helps to explain why tests with a high rate of false positives will still be endorsed, even if their overall cost outweighs potential gains.

This is not to say that screening doesn’t save lives and that it’s not one of the essential medical services physicians can provide. Rather, this article aims to emphasize that interventions should not be the first line of defense in tackling the biggest medical issues of our time: diabetes, heart disease and cancer, just to name a few.

So what can we do?

We need to change the emphasis of our healthcare system and move away from screenings and, instead, towards recommendation of behavioral and lifestyle changes that promote overall health. Many organizations are working at creating powerful and sustainable change, such as the Lown Institute, which is “dedicated to transforming the healthcare system by protecting patients from overuse, underuse, and misuse of medical tests and treatments.” Vikas Saini, president of the Institute, believes that “many doctors opt for drugs because they want to do something right away without having to rely on the often-unhealthy environment beyond their office walls,” where any meal can be “super-sized” and sedentary lifestyles are the norm.

Our current healthcare system encourages doctors to believe that their best resources are pills and procedures, rather than proactive advice. Hopefully, though, as more studies regarding the effectiveness of screening techniques are conducted, we will be able to modify the system so that we can achieve the best of both worlds, and keep the maximum number of patients safe and healthy. From making lifestyle and behavioral advice a bigger part of primary care, to teaching patients how to self-screen for breast lumps or melanomas, we can shift the focus from intervention to prevention and create a more efficient, cost-effective and successful healthcare model.


Sarafino, E. P. & Smith, T. W. Health Psychology: Biopsychosocial Interactions. New York, NY: John Wiley & Sons, 2014.



Independent UK Panel on Breast Cancer Screening (2012). “The benefits and harms of breast cancer screening: an independent review.” Lancet, 380, 1778-1786.



About The Author

"I am a Senior at Princeton University, pursuing a major in Psychology and preparing for a career in medicine and journalism. I have worked as an intern for the New York Stem Cell Foundation (NYSCF), the Peter C. Alderman Foundation (PCAF), the Pulitzer Center on Crisis Reporting in Washington, DC., and The Children's Hospital of Philadelphia. My work for the Peter C. Alderman Foundation included a three-week trip to Uganda and Kenya visiting mental health clinics, conducting interviews with patients, co-writing a blog, and assisting with data collection at the annual African Mental Health Conference in Nairobi, Kenya. While studying at Princeton, I pursue my interests in global health and health journalism as the editor for the Neuroscience/Psychology section of Innovation Magazine: the Princeton Journal of Science and Technology. I worked at the Pulitzer Center on Crisis Reporting as the Global Health Projects intern. In learning how to be a better journalist, I was able to aid in Pulitzer's efforts to tell the stories of individuals, not only their circumstances."