So which group of students do you think would be more likely to get poor grades: the kids who watch more than three hours of TV a day or the ones who drink two or more cans of soda per day? According to a summary of a study by Washington state health and education leaders, it’s the pop drinkers! Say what? Seriously?

Yep, and what’s more, the article also states that those pop lovers are also more likely to report poor grades than those who skip breakfast or don’t get enough sleep. At least, that’s the way the results were reported in a brief article published in the Oregonian newspaper a few weeks ago. My husband subscribes to an electronic clipping service which sends him all kinds of education-related articles, and he shared this one with me. I thought it would be interesting to share it with you, but then I decided to go in search of the actual report itself. I wanted to get a little more info on the study and check out the statistics for myself, and I’m glad I did.

As I compared the charts and wording contained in the report (”Research Review: School-based Health Interventions and Academic Achievement”), I realized that my cursory reading of the Oregonian article had led me to incorrectly interpret the report’s conclusions. And it’s probably important to know that the results were based on a classroom survey called “Healthy Youth Survey” given to eighth-graders, so they are self-reporting. It asked questions about 13 different health risk factors, including substance abuse and chronic health issues as well as nutrition (the soda-drinking) and physical activity (the TV-watching). Students were defined as being academically “at risk” if they stated they regularly got Cs, Ds or Fs. The researchers included the “C” students, reasoning that students tend to “over-report” their grades (that sounds reasonable!).

What became more clear to me as I checked out the statistics is that each risk factor actually wasn’t being compared with another. Instead, the observation was the difference between, say, those who got more than eight hours of sleep per night and those who did not. The overall conclusion was that “for each specific risk factor, the difference in academic risk by health risk factor was statistically significant, including after adjusting for gender and socioeconomic status.” (Except, I would note it would appear, whether or not a kid got five or more servings of fruit and vegetables a day. Don’t tell the kids!) Hmm, okay . . . but didn’t the article about the report  say something else? Not really, but it sure didn’t state the results very clearly, and left a lot open for misinterpretation by what it didn’t say.

ACTUALLY,  students who drink two or more sodas a day are twice as likely to receive failing grades as those who drink less than that. That percentage is greater than the percentage of students failing who watch more than three hours of TV per school day versus those who watch less than that, or the percentage who fail while getting less than eight hours of sleep a night versus those who get more. And, besides arriving at the fairly obvious and logical conclusion that “healthy” kids tend to do better in school than those who are not, the study doesn’t attempt to explain the correlation between heavy pop consumption and poor grades.

What I learned (or re-learned) from all this is that it’s not a good idea to rely on a secondary source (like an article, political ad or biased commentator) to explain or interpret the results of some study or survey. Key information can be omitted or inaccurately portrayed (intentionally or not) to arrive at conclusions that are unsupported by the original facts.

Oh, and I’m glad my mom didn’t let us drink pop, watch much TV or stay up late when I was in school!

– Patty Vanikiotis, proofreader