Disease Control and Prevention reports:
Body Mass Index is a reliable indicator of body fat for most children and teens. BMI is calculated from a child's weight and height is used as an easy-to-perform method of screening for weight categories that may lead to health problems.. For children and teens, BMI is age and sex specific and is often referred to as BMI for age.
The Center for Disease Control and Prevention reports BMI for age growth charts for girls as well as boys to obtain a percentile ranking. Percentiles are the most commonly used indicator to assess the size and growth pattern of individual children in the United States.
The following table provides weight status categories and the corresponding percentiles and BMI range for 10 year old boys in the United States.
Health officials of a Midwestern town are concerned about the weight of children in their town. For example, they believe the BMI of their 10 year old boys is normally disrtubuted with the mean 19.2 and standard deviation 2.6
In a report, use the following information to
1.) Compute the proportion of 10 year old boys in this town that are in the various weight status categories given the BMI ranges.
2.) Discuss whether the concern of health officials is justified,
Weight Status Category
|
Percentile Range Category
|
BMI Range
|
Underweight
|
Less than 5th
|
Less than 14.2
|
Healthy Weight
|
Between 5th and 85th
|
Between 14.2 and 19.4
|
Overweight
|
Between 85th and 95th
|
Between 19.4 and 22.2
|
Obese
|
More than 95th
|
More than 22.2
|