Children at Trinity and Columbus Elementary Schools are the most obese in the New Rochelle public school system, according to a new report published by the New Rochelle Board of Education. 14% of students at the two schools have a Weight Status Category of 99% or higher. Isaac Young middle school students are the most overweight with 48% having a WSC over 85%.
The study, prepared by Dr. Adrienne-Weiss and Registered Nurse Barbara Ehrenreich uses height and weight measurements to determine whether a child is overweight (85th percentile or higher) or obese (99th percentile or higher). Weiss also disclosed for the first time that the district is combining data taken from pediatrician reports and reporting additional information on asthma, diabetes type 1, diabetes type 2, hyperlipidemia and hypertension.
In presenting the data to the school board last month, Dr. Weiss admitted that after 4 years of collecting data she does not know what is being done with the data. She said she imagines it is being sent to the Center for Disease Control. In their report, Weiss and Ehrenreich express the hope that the New York State Department of Health will use the data to providing funding to help parents create a healthy home environment for their children.
In her presentation to the board, Dr. Weiss described how she uses body mass index or "BMI" data to identify and treat obese children despite the well-established fact that BMI is not appropriate for individual diagnosis.
Ancel Keys, the obesity researcher, who coined the term "Body Mass Index" in 1972, borrowing a formula developed by a Belgian mathematician in 1832, specifically stated that BMI was not appropriate for individual diagnosis.
When you understand how the formula was developed and why, the reason BMI is not appropriate is obvious.
Belgian polymath Adolphe Quetelet devised the equation in 1832 in his quest to define the "normal man" in terms of everything from his average arm strength to the age at which he marries. This project had nothing to do with obesity-related diseases, nor even with obesity itself. Rather, Quetelet used the equation to describe the standard proportions of the human build—the ratio of weight to height in the average adult. Using data collected from several hundred countrymen, he found that weight varied not in direct proportion to height (such that, say, people 10 percent taller than average were 10 percent heavier, too) but in proportion to the square of height. (People 10 percent taller than average tended to be about 21 percent heavier.)
In her presentation, Dr. Weiss stated that Weight Status Category -- how a child/teen’s BMI looks on a growth curve -- is similar to the height and weight curves plotted routinely at pediatric office visits. This is entirely untrue. There is no logical reason why the height of a person squared divided by their weight would permit a medical diagnosis or why mapping that data onto a chart would make it more so.
In fact, the "obese" category in BMI includes the most fit athletes.
Talk of the Sound has covered the many inadequacies of BMI before.
So, why are medical researchers so enamored with BMI?
The cheap and easy BMI test allowed them to plan and execute ambitious new studies involving hundreds of thousands of participants and to go back through troves of historical height and weight data and estimate levels of obesity in previous decades…the popularity of BMI spread from epidemiologists who used it for studies of population health to doctors who wanted a quick way to measure body fat in individual patients. By 1985, the NIH started defining obesity according to body mass index, on the theory that official cutoffs could be used by doctors to warn patients who were at especially high risk for obesity-related illness. At first, the thresholds were established at the 85th percentile of BMI for each sex: 27.8 for men and 27.3 for women. (Those numbers now represent something more like the 50th percentile for Americans.) Then, in 1998, the NIH changed the rules: They consolidated the threshold for men and women, even though the relationship between BMI and body fat is different for each sex, and added another category, "overweight." The new cutoffs—25 for overweight, 30 for obesity—were nice, round numbers that could be easily remembered by doctors and patients.
And government officials and school administrators love the idea that by quantifying an "epidemic" tax dollars will follow.
Yet, BMI has nothing to do with health. It has to do with a Belgian mathematicians ideas about physiology based on a sample set of less than 1,000 Belgians taken in 1832. The more you know the more ridiculous the notion that BMI can be used for diagnosis, should determine government funding and or support proclamations that School A is fit and School B is unfit.
The following chart illustrates the large percentage of inaccurate "diagnoses" of being overweight or obese inhere in BMI; the upper left and lower right quadrants are all "false positives". That is a very large error rate.
Despite the many flaws, Dr. Weiss concludes that "students who attend school in the southern part of the district have a more pronounced problem with weight than our students in the northern part of the district."
On a technical note, as is typical for analysis from the school district, Dr. Weiss inaccurately states there are "11% more middle school students at IEYMS that are overweight than those at ALMS."
No. The report states that the overweight level at Albert Leonard is 37% and at Isaac Young is 48%. That is a difference of 11 basis points but the percentage difference is 30%.
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