Parents of children in most elementary grades in Minnesota’s Independent School District 191 receive an annual notice with potentially life-altering data for their children—and they are not state test scores, attendance rates or grades.
The notice contains the child’s body mass index (BMI) score, which estimates whether the student has excess body weight relative to his or her height, age and sex.
The 10,200-student district is among a number of states and individual districts nationwide that are measuring children’s BMI scores and notifying parents of the results, hoping such notices will serve as wake-up calls to parents about their children’s weight and the health risks of obesity. Parents of students whose BMI scores are in the top 5 percentiles—95th and above—are informed by their district that their child may be overweight and at risk for complications such as high blood pressure, high cholesterol and diabetes.
In 2003, Arkansas became the first state to mandate BMI screening and parental notification. Pennsylvania and Tennessee have followed suit. But experts say that there is not yet enough research to show that these programs work, and concerns have been expressed about the BMI measurement system’s possible effects on self-esteem. For example, the BMI measure itself is not perfect and can falsely label a student who is of a more muscular build as obese.
Is BMI TMI for Parents?
Independent School District 191, which serves three Minneapolis suburbs, was approached about four years ago by University of Minnesota researchers about starting a BMI screening program.
Concerned about the national trend toward increased childhood obesity, the district with the university’s cooperation began a BMI screening program in elementary schools in the 2004-2005 school year to alert parents to the issue of obesity, says Dawn Willson, the district’s director of health services. “Nationally, the statistics of the BMI are increasing along with health problems that are resulting from the increased weight and BMI,” she says.
But are parents receptive to that kind of wake-up call? Parents in the Minnesota district were generally supportive—with some conditions: that the screening should be accurate and done privately and that results should be kept confi dential from children, says Willson, whose district allows parents to opt out of the screening program.
Some critics of BMI screening programs have questioned their potential effect on a student’s self-esteem and body image, but more research is needed to determine the validity of those concerns, says Allison Nihiser, a health scientist at the Centers for Disease Control and Prevention, which makes no recommendation for or against BMI screening-andnotification programs.
The Jury Is Out
For districts that just use BMI, height and weight are taken to estimate body fat. Under the BMI formula and comparison chart, a 13-year-old boy who is 5 feet 2 inches tall and weighs 138 pounds would be at the 95th percentile—the threshold at or above which indicates obesity, experts say. (BMI can be calculated using computer programs, or the Centers for Disease Control and Prevention’s calculator or its sex-specific CDC chart, both of which are available at www.cdc.gov.)
So far there is “insufficient evidence” concerning the eff ectiveness of such BMI parental notification programs, says Nihiser. “There is some evidence showing that it’s a promising approach; however, there is a lack of research on the attitudinal, knowledge and behavior impacts” on children and parents, she says.
The CDC doesn’t object to districts’ collecting BMI data for their own use to judge the overall health of students, known as “surveillance” screening.
A survey by the University of Arkansas for Medical Sciences found that nearly one in five overweight students expressed embarrassment about BMI results. Worries about stigmatizing students—as well as testing burdens on districts—nearly caused Arkansas legislators to scrap thestate’s BMI program last year. State legislators instead reached a compromise with Gov. Mike Bebee to reduce screening to kindergarten and even-numbered grades.
The policy revision also allowed parents to opt out in writing, and it exempted high school juniors and seniors from screening.
Because of self-esteem concerns, pupils in the Hot Springs (Ark.) School District are not allowed to see their own heights and weights, says Superintendent Joyce Craft. But parents are informed so that they can consider lifestyle and diet changes for their children.
A key decision in developing a BMI screening program is what to tell parents whose children have BMI scores that are considered too high.
Nihiser says that a system to refer parents to medical providers is important because BMI is not a diagnostic test, but a screening tool. A medical provider is needed to examine, diagnose and treat obesity, she adds.
The East Penn School District in Emmaus, Pa., near Allentown, implemented a BMI notification program in 2001-2002, three years before the state mandated that all Pennsylvania districts conduct such programs.
The notification letters direct parents to seek a medical provider if their children fall into the BMI category that indicates they may be overweight. But the letters do not contain recommendations regarding diet and exercise, says Michael J. Murphy, the district’s director of student services.
The district did not want to step out of its “limited role” by giving specific direction to parents, “because ultimately it is up to the parents what they are going to feed their children and what steps they are going to take to improve their health,” Murphy says. The district connects needy students with health care programs.
Nihiser says that BMI-screening districts need to refer parents to health providers and include tips for healthy eating and physical activity.
The Minnesota district gives parents tips for healthy eating and lifestyle choices, but this year it began also recommending that parents whose children’s BMIs are in the top five percentiles consult a medical provider. “The intent is to try to give parents the information in a nonthreatening way,” Willson says.
The Minnesota district has a health clinic for student use. Seeing a doctor is important because high-BMI kids may need to be assessed for high blood sugar, cholesterol or blood pressure, she says.
Comprehensive Program Needed
Districts embarking on BMI screening should do so as part of a comprehensive anti-obesity strategy that includes elements such as a wellness policy and increased student time for physical activity, Nihiser says.
Minnesota’s Independent School District 191 saw the BMI program as “the start of a districtwide movement to be healthier,” Willson says, which included implementing a new wellness policy calling for restrictions on “junk food” vending and ensuring a 30-minute daily average of physical activity in elementary grades. The district also off ers at least two choices of fruits and/or vegetables at each meal.
The district is not alone in making such reforms, according to a national CDC survey. Between 2000 and 2006, the number of districts banning junk food in vending machines increased from 4 percent to 30 percent. Arkansas, as a state, was among them. More districts during the same time period began requiring that elementary schools have regularly scheduled recess, and fewer districts were serving French fries, the survey states.
Do BMI screening-and-notification programs work? Since the inception of its BMI screening program, Arkansas has seen its childhood obesity rates remain relatively stable, while other states have seen increases in percentages of overweight children. But it’s unclear whether Arkansas’ screening alone can be credited for the stability, given the statewide push to ban junk food and increase physical activity in schools.
The study by the University of Arkansas for Medical Sciences found that parental awareness of obesity-linked health problems increased following the start of the BMI program.
But overall the study did not find tremendous changes in family nutrition or physical activity patterns at home, although there was a slight uptick in the percentage of parents limiting family consumption of chips, sodas and sweets.
The Minnesota district has seen its overall rates of children in the top five BMI percentiles drop from 15 percent in 2005-2006 to under 13 percent this school year, though some individual schools saw increases, Willson says.
Even if the approach proves to be eff ective, BMI screening should not be regarded as a panacea. And districts need to tread carefully.
“There should be a comprehensive strategy to address childhood obesity,” Nihiser says. “BMI is just one approach, and that approach has not been proven to be effective yet.”
Kevin Butler is a contributing writer for District Administration.