Final answer:
A 13-year-old boy with a BMI at the 97th percentile is classified as obese, because a BMI higher than the 95th percentile for children of that age indicates obesity. BMI percentile ranges are used to assess weight status in comparison to peers, though BMI does not account for muscle versus fat mass.
Step-by-step explanation:
A 13-year-old boy whose body mass index (BMI) is at the 97th percentile would be classified as obese. In children and adolescents, obesity is generally defined by comparing their BMI to reference values tailored to their age group. A child with a BMI that is greater than the 95th percentile for their age is considered obese. Since the BMI of this boy is at the 97th percentile, it exceeds the obesity threshold, indicating that his BMI is higher than that of 95 percent of boys of the same age.
It is important to recognize that while BMI is a useful tool for assessing weight categories in a population, it does have limitations for individual assessments. BMI does not differentiate between fat and muscle mass, which might lead to misclassification, especially in muscular individuals and athletes.
The Centers for Disease Control and Prevention (CDC) and other health organizations use these percentile ranges to help indicate levels of weight status among children and teenagers, which can be crucial for identifying potential health risks associated with overweight and obesity, such as cardiovascular disease, type 2 diabetes, and other chronic conditions.