A study of obesity risk in children in a head start program used a food score calculated from a 45-question food survey to predict body mass index (BMI) percentile in these children 18 months after the initial survey. The study enrolled 20 children. The researchers used a linear regression model for the prediction of BMI percentile. The food scores ranged from 45 to 245. Two computer programs the researchers used to obtain their regression model and related calculations also provided two intervals for a child with food score 150. Interval I₁ = (56.13, 67.35) and interval I₂ = (36.35, 87.13). These intervals, respectively, are called: A)the regression and residual intervals. B)the mean interval and the regression interval. C)the interval for prediction of value and the interval for regression. D)the interval for mean BMI and the prediction interval for food score 150.

Question

Quizplus · Accepted Answer

The first interval (56.13, 67.35) is likely the interval for the mean BMI for children with a food score of 150, indicating where the average BMI percentile falls for this group. The second interval (36.35, 87.13) is broader and is the prediction interval, which accounts for the individual variability around the predicted mean BMI percentile for a child with a food score of 150, thus providing a range where an individual child's BMI percentile is likely to fall.

A Study of Obesity Risk in Children in a Head