A parent's guide to understanding medical studies

Educate yourself with our tips on how to read and interpret medical research

Have you ever read a story about results of a medical study and wondered what it means for your family? These days, access to medical studies is as simple as a mouse-click away so parents can educate themselves on the most up-to-date research. This can be both a blessing and a curse. But with the slew of provocative health reports we are deluged with on a regular basis, making decisions based on fear,  @font-face { font-family: “Cambria”; }p.MsoNormal, li.MsoNormal, div.MsoNormal { margin: 0cm 0cm 0.0001pt; font-size: 12pt; font-family: “Times New Roman”; }div.Section1 { page: Sectio not facts, can be tempting. Before playing Dr. Mom (or Dad), here are a few tips on how to read, and critically interpret, a medical study.

Learn the lingo
There are three major types of studies: a double-blind, randomized controlled trial (RCT), a meta-analysis and an observational study. One isn’t necessarily better than the other, they simply reach scientific conclusions in different ways. Here’s how they work.
 
RCT
RCTs investigate whether or not a drug or intervention works by randomly, or blindly, assigning participants into two groups: those who receive the treatment and those who don’t. These studies are particularly useful for eliminating bias and help parents understand the treatment outcome of a specific drug. For example, does the antibiotic amoxicillin help alleviate the symptoms of a sore throat in children?

Meta-analysis
A meta-analysis is a method of combining data from several RCTs into a larger, systematic review. By statistically pooling information from a number of independent studies, researchers, and parents, can be more confident the chance of spurious results (i.e. false positives or false negatives) are minimized. The Cochrane Collaboration is a great resource for moms and dads who want to access these large-scale studies to learn more about the potential risks and benefits of various medical treatments. For example, what does the vast majority of the research say about the effectiveness of various interventions for preventing obesity in children?

Observational studies
An observational study is one that follows a group of individuals exposed, unintentionally, to a variety of potentially harm-causing agents, including pollution or carcinogens, and attempts to make a correlation between exposure and disease. For example, do children who live in large cities have a greater risk of developing asthma? These studies provide parents with a wealth of scientific information, that, for ethical or practical reasons, could never be gathered using an RCT. But they also come with a very important caveat: just because two things are linked, one does not necessarily cause the other.
Become a medical sleuth
It’s smart to look at every scientific study with a healthy dose of skepticism, says Dr. Eyal Cohen, a physician at The Hospital for Sick Children in Toronto. Keep in mind the majority of studies in medical science are observational, which only suggest correlation, not causality. There’s a big difference between a report that proves A causes B, versus one that simply links A and B. Kids who chow down on non-organic strawberries may indeed have a greater incidence of ADHD, but this could be due to chance alone. Another example? The infamous, and now discredited, 1998 Lancet study by Andrew Wakefield that claimed the measles, mumps and rubella (MMR) vaccine was linked to autism, which scared some parents into avoiding the triple vaccine altogether. “Children are generally diagnosed with autism in the second year of life and they are vaccinated with MMR in the second year of life, too,” says Dr. Cohen. “It becomes particularly difficult to separate out whether these [types of] relationships are real or not. Detecting bias in medical studies is also important. Is the author’s research sponsored by a drug company, as is often the case for RCTs? If so, I always call a red flag,” he says.

Don’t let fear rule
Before you make any drastic moves, remember individual studies are rarely a reason to panic or make a change. “Most new research doesn’t have appreciable effects on health. Either the findings are refuted or they’re found to be not that important 10 to 20 years down the road,” says Dr. Cohen. “I wouldn’t make decisions about my health, specifically decisions that have implications for your lifestyle, your finances or the risks you take in your children’s life, based solely on one study you read in the newspaper.” Instead, look to organizations such as the Canadian Pediatric Society  or the American Academy of Pediatrics for well-supported position statements on everything from nutrition and injury prevention to mental health and allergies. If you’re still in doubt, consult your child’s doctor. In the end, the best advice for parents is to trust your gut: “Motherhood is usually right way more often than any researchers are,” he says.