Every newscast seems to include that phrase. "New research shows" this, "the latest study shows" that. Whether on TV, in print or online, health news is a hot topic.
Evaluating what the latest news means for you and your family isn't always easy. Should you stop—or start—eating certain foods? Is this new drug better than the one you're taking?
Of course, your doctor is your best resource for questions about your health.
But learning more about how studies are done and how findings are reported can help you translate media reports from useless noise into useful news.
Types of studies
Studies can be conducted in a variety of ways. Each of them has its own strengths and weaknesses.
Two of the most common you may hear about are observational studies and randomized clinical trials.
Observational studies. Researchers observe a group of people for a period of time. There are several types of observational studies. For example, the participants might keep records of their diet or other habits, but the study doesn't include any treatment. The researchers see who develops a certain disease or condition and who doesn't, and what the two groups have in common or how they differ.
Strengths and weaknesses: Observational studies can suggest a direction for further research, according to the National Institutes of Health (NIH). But they can only suggest an association between things. They can't prove cause and effect.
Clinical trials. Participants are randomly divided into two or more groups. A control group gets no treatment—such as a placebo—or a lesser treatment, such as education. A study group is given treatment—a medication, perhaps, or a special diet. Results between the groups are compared.
Strengths and weaknesses. A well-designed clinical trial is considered the gold standard of studies. Clinical trials are often conducted in several phases, with each phase including a larger number of participants.
Clinical trials can't always be used, notes the NIH. For example, it would be unethical to ask people to start smoking or eating an unhealthy diet.
Other terms you may hear when research is described:
How results are reported
How a study's findings are reported can make a big difference in people's reaction to the information.
For example, what if you heard that people taking a certain medication had a 100% higher risk for a disease than people not taking it? That sounds terrible.
But what if you heard that people taking the medication had twice the risk for this disease? That's maybe a little less alarming, but it still sounds high.
Now consider hearing this: The disease normally occurs in about 2 of every 10,000 people. If all those people took the medication, that number would rise to 4 out of every 10,000 people.
These are all the same findings. The difference is that the first two are examples of relative risk—differences reported as a ratio or percentage. The last is absolute risk—the difference as an actual number.
Both are valid ways to report the results of a study. But sometimes knowing the absolute risk is more meaningful.
Questions to ask
Here are some questions to ask that can help you better evaluate medical news:
Seek more information
Keep in mind that one study is rarely the last word on a topic—or a reason to dramatically change what you're doing to protect your health or control a disease.
Results need to be replicated by other researchers several times before they are accepted as good practice.
Of course, that always leaves open the possibility that a new study might disagree with earlier findings. And although that can be frustrating to consumers, it's part and parcel of the scientific process.
That process should involve asking questions. It should also involve working with your doctor, finding out what works best for you today, and being open to making changes as needed.