Two studies that were recently published in reputable journals have caused dental professionals to question their protocols. While we should always be open to new and emerging science, it’s important not to let sensationalized headlines or a research paper conclusion be your new gospel before jumping on the latest bandwagon.
Although I slept through much of my research methods in college, I now recognize the importance of those classes—especially in today's clickbait-filled world. Critical thinking is a crucial part of being a clinician, so when doing research, don’t cut corners and read more than just the abstract.
Essential research components
Here are five key components to consider when evaluating whether the research you’re viewing is sound and applicable:
1. Check the journal
Just because it’s on PubMed doesn’t mean it’s reputable. In fact, there are journals out there that are considered predatory or pay-to-play; some people have intentionally published shoddy work just to see if they could get away with it (spoiler alert: they did!). There’s even a website called Beall’s List that will let you know if it’s a reputable journal.
However, even with credible sources, you need a discerning eye. It seems even the academic world is not immune to jazzing up titles or headlines to get attention despite possibly misleading the reader. Sometimes studies are released “preprint,” which means they have not been peer-reviewed before publication. This type of content is still worth reading, but make sure to check back in a couple of months to see if it stood up to scrutiny.
2. Who wrote it?
What are the authors’ credentials? Does their expertise have anything to do with what they’re researching? I mean, would you trust research about caries from, say, a plumber?
To identify authors or studies that have been retracted, you can use the Retraction Watch Database. Just enter a researcher's name and see if there are any invalid studies published under their authorship.
You should also keep an eye out for any conflicts of interest. I’ve read many studies funded by a company or written by an employee that skews the data to benefit their product.
3. Hierarchy of study methods
This is where it gets sticky for me. While there is no "correct” way to do research, paying attention to the research design will give you confidence in the quality of the study (or lack thereof) and its applicability to patient care. The higher the level, the less risk of bias.
- Meta-analysis and systematic reviews with randomized controlled trials
- Single randomized control trial, preferably blinded
- Controlled trial but not randomized
- Well-designed case-control or cohort studies
- Systematic review with ONLY qualitative studies without data
- Results from a single descriptive or qualitative study
- Expert opinions
- Animal research
- In vitro research
4. Correlation versus causation
I get caught up in this debate, especially when it comes to linking oral pathogens to systemic health issues. While I fully believe that the pathogens in a patient's mouth directly affect their other bodily systems, we don’t have a causal link to everything; it’s just a correlation. Linking everything up will take time.
Studies with a small sample size, a short duration, or even a lack of randomization can conclude something that is simply a coincidence. Seeing a study repeated time after time can offer confidence to the conclusion. Also, looking to see how often a study has been cited might give you a clue to its validity.
5. Results don’t match the conclusion
As a former abstract-and-conclusion-only reader, I have been led down a false path more than once. Making sure results align with a study’s conclusion is the time-consuming part of doing research. The goal is to remove bias, but it creeps in, intentional or not.
Research pointers to consider
Begin with your mind in critical thinking mode. Take notes as you go and jot down what you don’t understand; this is where having a research buddy is helpful. The more time you take to discern facts and figures, the more red flags will stand out to you. Like anything else, reading research effectively takes practice. You may even want to find trusted expert bloggers and read their take on the research. You might not agree with their points, but you’ll start to understand where the holes are.
