What to Believe When Health Claims Conflict

One day aspirin is good for you; the next day's report says it's linked to some sort of rare disease. If you follow medical news closely, it's not that surprising to find contradictory or conflicting information during the same week's news. Trying to stay on top of medical information—and use it to improve your health—can be quite challenging. Here are some tips to help you read between the lines and tease out the most relevant information:

  1. Read carefully and be critical of new medical findings. It's important to determine if the information is current (website information can go long periods without being updated) and how the particular study was conducted.
  2. Be sure you are comparing apples to apples. For example if you are comparing studies about using aspirin as a blood thinner be sure the populations being evaluated by the study are similar. If the study looked at men over 65 with diabetes that may not be relevant to your situation unless you are over 65 and have diabetes.
  3. Know the difference between a clinical trial, an animal study, and an observational study. According to the National Institutes of Health, a clinical trial is: "[a] research study that tests how well new medical approaches work in people. Each study answers scientific questions and tries to find better ways to prevent, screen for, diagnose, or treat a disease."

Clinical trials may also compare a new treatment to a treatment that is already available. Every clinical trial has a protocol—set of standards—for conducting the trial. The protocol describes the purpose of the trial and how it will be conducted. There are rules about who can participate in each study. Some studies need healthy people; others are looking for just men of certain ages or postmenopausal women, for people with particular health conditions.

Clinical trials are usually conducted in distinct phases, each being a necessary step toward FDA approval of the treatment option being evaluated. Large clinical trials are expensive and take years, so they aren't usually undertaken until a large body of supporting evidence has accumulated and points to a claim that is plausible enough to be worth the investment.

Observational studies have less specific controls. They look at what happens to people who act in a certain way in their everyday lives. Using aspirin as an example again, an observational study might look at men over 50 who exercise for 30 minutes four times a week and take aspirin daily versus the affect of daily aspirin on men over 50 who don't participate in any regular exercise.

An animal study is quite simply a study done on animals that may have application for humans.

Consider the impact of randomization. Clinical trials can be randomized which means the comparison groups aren't necessarily alike.

Size matters. The larger the study, the more reliable the results because the margin of error will be smaller. Smaller studies have more uncertainties. If a small study is randomized the results may not be very well balanced.

A double-blind, placebo-controlled randomized clinical trial is the gold standard for scientific research. This is a large study in which participants are randomly assigned to either an experimental or a control group. Neither the participants nor research evaluators know which person is in which group until the study is completed.

Consider the source. Medical studies are just one source of information. If you'd like to learn more about a particular disease or health topic, there are many reputable websites you can visit:

Finally, there's no substitute to a discussion with your health care provider. To get the most from an upcoming appointment, be prepared. Do a little online research ahead of time and formulate some questions. Jot them down and bring it along with you on the day of your office visit. A one-on-one chat just may turn out to be the most reliable and up-to-date information you find.




The National Institutes of Health


The New York Times

The Alzheimer's Disease Cooperative Study