If a career in public health academics and research sounds like your idea of heaven, a PhD in public health can be your ferry across the Jordan. You can train the next generation of public health experts or devise programs that improve healthcare delivery and practice, all from the cozy confines of an ivy-lined building.
One student works in a lab to learn how environmental exposures experienced at an early age can affect the gut. Another investigates ways to prevent and treat Alzheimer's disease. A third—a self-described math nerd—works on statistical models that help determine cause and effect in disease research.
Disparate projects (all currently underway at this writing, FYI) to be sure, but they share at least one thing in common: those undertaking them are all pursuing a PhD in public health.
What is "public health," exactly? According to the Centers for Disease Control and Prevention (CDC), it's "the science of protecting and improving the health of people and their communities." That's a broad umbrella covering many endeavors, from developing public health policy to researching infectious diseases. While doctors and nurses staff the front lines to combat disease, graduates of public health PhD programs provide essential support by determining whether treatments are working and devising improved approaches to community health.
Graduate schools offer public health degrees in a variety of disciplines. In this guide to PhD in public health, we'll cover:
The term "public health" encompasses five core disciplines:
In behavioral science, you study how behavioral, social, and cultural issues contribute to public health issues. For example, you may study how smoking causes disease, and then apply the theories you learn in graduate school to developing public health intervention and social work programs.
Biostatistics applies statistics to public health fields. In this discipline, professionals break apart and interpret data to work on pressing public health issues. For example, experts in this area can apply statistical methods to answer questions about a drug's safety or the risk factors for cancer in a population. You can apply your biostatistics knowledge of dissecting data in a wide range of sectors, from agriculture to genetics.
Environmental health scientists explore how the environment affects both individual and public health. They are frequently honored as public health heroes for their work. Pressing issues include air pollution, chemical pollutants, climate change, and drinking water quality. An environmental health scientist can work as an industrial hygienist—someone who protects employee health in the workplace—or as a safety professional in the private sector, government, or at an environmental consulting firm.
Epidemiology is perhaps the best-known field in public health programs. Epidemiology is the area of study that works to find the causes of diseases and health events by looking into patterns and risk factors.
Fun fact: epidemiology originates from the Greek words epi (meaning upon), demos, which translates to people, and logos, meaning the study of. So, as an epidemiologist, you'll be literally studying what befalls the people. Areas that epidemiologists typically investigate are foodborne illnesses or the flu, but they can also study gun violence and natural disasters.
Health policy and management focuses on the policy aspect of healthcare—delivery, quality, and costs. The University of North Carolina at Chapel Hill's Gillings School of Global Public Health, for example, aims to provide students in its Department of Health Policy and Management "with the skills to conduct innovative health services/health policy research that can be used to foster the most effective ways to organize, manage, finance, and deliver high-quality healthcare."
These are the five primary public health disciplines, but they are not the only ones. Other public health fields include:
Students explore health trends around the world and the interconnectedness of communities regardless of origin. Topics may compare national health policies, social disparities, and common health needs of each population.
Public health scholars with a focus on genetics trace the causes of disease passed down through generations and within specific communities. These studies can help predict the health needs of a population, as well as connect research findings to public policy.
The curriculum may explore the disparities among different cultures when it comes to nutritious food supply. Students may base their theses on topics like food deserts, community outreach, or disorders linked to nutritional challenges.
Doctoral candidates can evaluate what contributes to a sustainable society for the health and wellbeing of pregnant people and their children. Research may guide laws, government support, and access to medical care for these communities.
Different schools might have slightly different names for these disciplines (at University of Rochester, for example, biostatistics is grouped with computational biology).
Your background and interests should determine the discipline that best suits you. If you're currently an undergraduate student, you have plenty of time to decide. You don't have to major in the subject in which you pursue a PhD. If you are further along (perhaps considering, or studying for, a master's), you may have already found your track. Ultimately, any of these paths could lead to jobs in government, academia, and the private sector.
The time commitment required for a PhD in public health can vary from school to school and program to program. In general, earning a PhD takes between four to six years of full-time study. Completing coursework typically takes two years, followed by written and oral exams, research or fieldwork, and a dissertation that presents your work.
This is a terminal degree, and as you might expect, the entire process is difficult. The dissertation is particularly challenging. It culminates in a dissertation defense, during which you will face a committee of scholars reviewing and questioning your work. Recent studies suggest that only about 60 percent of PhD candidates in the life sciences, social sciences, and mathematics complete their dissertations within ten years.
Prerequisites vary from program to program. But in general, schools require applicants to submit the following:
Students will submit their transcripts from an undergraduate and, if applicable, a graduate degree as well. Many schools also require a GRE score of at least 300 (if less, some programs will accept a strong portfolio to balance out an application).
The majority of admissions directors look for candidates with at least two or three years of relevant experience in the field. Students should outline these details in a resume or a cover letter.
Successful candidates must have a foundation of research training and experience, as well as writing samples to submit in their application.
Professionals in the field should be able to vouch for a prospective student's experience, career goals, and demeanor to ensure they are a good fit for each unique program.
This is the applicant's opportunity to explain why this specific program supports their career path and what they plan to contribute to the cohort. The university may ask a specific question or ask the student to explain their dissertation plans.
Some schools of public health require a master's, but not all do. Many programs will admit you on a master's/PhD track so that you will earn both degrees from the same university. Other programs may require that you have an undergraduate degree in the field, but that is typically not the case. Exams and certifications to complete a PhD in public health may vary depending on the school's program, so dig deep during your degree program search.
For example, the University of Washington - Seattle Campus requires that applicants for a PhD in biostatistics hold a degree in math, statistics, or a biological field, with the equivalent of 30 or more credit hours in classes that include linear algebra and probability theory. Two years of calculus are also required. For its nutritional sciences program, the university accepts bachelor's degrees in any field but specifies that applicants should demonstrate experience related to nutrition, dietetics, public health, or research. PhD candidates in epidemiology must hold a master's degree and demonstrate a strong background in health sciences, biological sciences, or quantitative sciences.
Once you're in a program, you'll focus on mastering the research tools within your specialty. Throughout your tenure, you'll have a wide range of opportunities to work on compelling projects alongside faculty.
Note: a PhD in public health should not be confused with a Doctor of Public Health (or a DrPH) degree. The DrPH doctoral program is designed for working professionals, often those who work in a clinical setting; the PhD is focused on academics and research.
When looking at universities with PhD degree programs in public health, be sure to closely examine what kind of courses, research opportunities, and faculty make up the program. You'll want it to align with your career goals and interests so you're pursuing the best pathway. According to US News & World Report, top graduate programs in public health include:
Columbia offers two post-graduate public health degrees, the PhD in public health and a DrPH. The programs allow students to specialize in areas such as epidemiology, population and family health, and biostatistics.
Emory is based in the heart of Atlanta, which is known as the "public health capital of the world" (it’s where the Centers for Disease Control is located). Students study alongside experts in the Emory clinic, aiding in the treatments for Alzherimer's, AIDS, cancer, and other top pressing public health concerns.
Harvard PhD candidates have the option to concentrate in biological sciences, biostatistics, health policy, and population sciences. Admissions preference goes to students with specialized experience and research in their chosen area.
While JHU does not specifically offer a PhD in public health, it does offer a wide range of PhDs in more concentrated topics—such as epidemiology and policy and management—as well as DrPH in public health.
Ranked as one of the top public health schools in the country by US News and World Report, Michigan offers a six-term PhD that culminates in a dissertation.
Also topping the US News and World Report charts for public health programs, UNC Chapel Hill offers global access to research initiatives. Students can choose from a wide variety of specialities, including health behavior, biostatistics, and environmental sciences and engineering.
While some schools offer an online doctorate in public health (DrPH), online PhD programs are much rarer. We cannot recommend any at present.
There are two reasons to get a PhD in public health: to satisfy a passion to learn more about public health, and to improve your professional prospects.
If your life's goal is to immerse yourself in public health research and education and become a public health professional, then a doctoral degree in public health is your golden ticket. If you have what it takes to succeed at a prestigious program, you will be positioned to spend the rest of your life in public health academics and research.
If your goal is to make more money and have a greater impact on the field of public health, the answer is more complicated. It's possible to advance pretty far with just a Master of Public Health (MPH) degree. According to the US Bureau of Labor Statistics (BLS), in 2020 the median pay for an epidemiologist with a master's was $75,000 per year. And according to Fortune, someone with a master's in biostatistics can make $105,900 annually.
But some specific fields or jobs may require a deeper understanding of methodologies and applications, and an employer would want someone with a PhD. Pay rates, in general, go up—but how high depends on the sector. In academia, an epidemiology professor's salary averages at $94,000. Academic jobs are highly competitive, and applicants generally have to relocate for the job.
It's clear that people who seek a PhD in any discipline have a connection and a passion for that discipline—an intrinsic drive to gain a deeper understanding of the field. In the case of public health, professionals yearn to help and heal the world around them. If you have that connection, pursuing a rigorous PhD program can be worth your time, expense, and effort.
Take the example of the epidemiology graduate student in epidemiology who summarized her study of health disparities among socioeconomic and racial groups in a New York Times opinion piece. As a graduate student, she explains, she felt isolated as she pored over statistical models, peer citations, and data. At a conference, however, an attendee—who was not an academic—approached her to thank her for her work, saying: "I see myself in this research. This was a study meant for women like me." The encounter reminded her why she was drawn to academic public health. "I research for the sake of humanity," she said. "All researchers could use that reminder."
If you can imagine yourself saying that, a PhD in public health may be the right degree for you.