As a professor of Epidemiology, my primary goal is to teach my students how to read, critically analyze, and apply the results of an epidemiological study to create healthy communities. I want to empower my students to read research papers from beginning to end (not just the Abstract and definitely not skipping the Methods section). I want them to confidently read the literature, determine for themselves the strengths and limitations of the study, and be able to communicate the findings and any applications of those findings to a group of community members without any knowledge of epidemiology.
It is a BIG goal. It is an important goal.
It is my life’s work.
And I want to invite all of you into my classroom (so to speak). I want to provide you with a guide to reading the epidemiological research and the opportunity to read, discuss, and apply the findings of epidemiological studies with me.
Together — with improved literacy and the ability to see the strengths and limitations that are inherent in every study — we can fight misinformation, spot disinformation, craft strategies to improve health, and create healthy communities.
Remember: when we get the science wrong, there are very real consequences —
Trust erodes.
We fail to make decisions for the common good.
We fall victim to the lie that we can be healthy by just making the best decisions for ourselves.
People die.
And communities become unhealthy.
Are you ready?
Do you want to learn how to read, analyze, and apply the epidemiological literature?
Let’s get started with RULE #1.
Rule #1 is simple — there is NO perfect study. A gold standard does NOT exist.
That’s it. (Mic drop)
Seriously, I have heard far too often that the double-blind clinical trial is the gold standard epidemiological study or a descriptive study (which is often used to determine the number of cases of disease in a specific population) only provides value to researchers who want to do more research.
NO.
Not every health question we have can be answered with a double-blind clinical trial. Often it is unethical to use a clinical trial design to answer an important health question. For example, one of my senior research students is attempting to determine if college athletes are more likely to get injured on their dominant side or non-dominant side. If she were to conduct a clinical trial to answer her research question (which is rooted in her desire to decrease injuries among college athletes), she would need to injure college athletes INTENTIONALLY. Her research question cannot be answered with a clinical trial. So we are using another study design because intentionally injuring athletes to understand injury rates is completely unethical (and in case you are interested, she’s conducting a survey and asking athletes about injuries and their “sidedness”).
Clinical trials can also be impractical. Or too costly. Or they can take too long to complete.
Clinical trials are far from a gold standard for epidemiological studies.
And far from perfect.
And descriptive epidemiological studies, where we determine how many cases of a disease, like cancer, are in a community, are SUPER IMPORTANT. They are not merely used to help generate more research. Instead, we use these studies to help us allocate resources, design new health education campaigns, and target public health interventions. If we know that cancer is increasing in a town, maybe we need to increase cancer screening tests, increase uptake of the HPV vaccine, or work to decrease the number of individuals who smoke cigarettes. A simple study that tells us how many cases of cancer there are and maybe the increase in cases from one year to another is PRICELESS.
While no study is perfect, we conduct epidemiological studies that will allow us to create healthy communities.1
The science of epidemiology is valuable because it is used to improve the public’s health. Dr. Foege — former head of CDC and the epidemiologist responsible for designing the strategy to eradicate smallpox — states,
“The power of science is in the application. … It has to be applied in order to be powerful.”
The first rule of understanding epidemiological research is no study is perfect. And there is no gold standard study that will magically and perfectly answer the questions we have.
Every study will have limitations.
As readers of the epidemiological research, we must remind ourselves that the power of epidemiology is NOT in a perfect study; it is the application of the science to make incremental changes that will lead to the creation of healthy communities for all.
That’s it… your first lesson is over.
The power of epidemiology is in its application
(not in a quest for or expectation of) perfection.
Next Tuesday we’ll move onto The Three Things the Authors of the Epidemiology Study You Are Reading Assume You Know…
Be sure you are subscribed so you do not miss a thing.
Do you have questions about RULE #1? Or would you like me to share a homework assignment with you? Leave me a comment (like “sign me up” or “send the homework now”) and your email address. I’ll be sure to include an answer key!
Want to see an example of a study that was designed well and had a huge sample size, but did little to help us create health communities? Read the amazing Rachael Robertson’s summary of a huge study conducted in Sweden looking at wonky periods and the COVID vaccine. Rachael graduated from Allegheny College in 2017.