The BMI index is often used to determine cardiovascular risk, or risk for diabetes in a person. Different variables used, along with height and weight, are waist circumference and waist to hip ratio that have shown to be effective in determining risk (Savva, Laminsos, & Kafatos, 2013). The correlation comes from the two variables when one variable is associated with another that is higher or lower (Bennett, Briggs, & Triola, 2018). Waist circumference related to height and weight and can show level of obesity, and therefore determine risk for cardiovascular disease and diabetes (Savva, Laminsos, & Kafatos, 2013). Overall body fat percentage would be another useful variable in determining risk. If we measured body fat percentage with glucose levels, which determines if a person has diabetes or not, and made a scatter plot graph we may find a positive correlation between high percentages of body fat and high glucose levels. Not all people that are obese are diabetic though. So, we may find a moderate correlation where the correlation coefficient of r is between 0.3 and 0.7. Looking at the data we can also see a positive slope of 1.028 which means the line of best fit is increasing with data points in close proximity which verifies a strong correlation. So, we can say that there is a correlation between obesity and diabetes, but obesity is not necessarily the cause of diabetes. On a scatter plot, the weight of patients may be on the x axis with weights ranging from 200 to 300lbs. They axis would be glucose ranging from 200-300. The results could show a correlation coefficient of 0.8319 and a coefficient of determination of 0.6921 which is actually a strong positive correlation. The conclusion is that it is best to control body weight to decrease the chances of having diabetes
Bennett, J., Briggs, W., & Triola, M. (2018). Statistical Reasoning for Everyday Life (5th ed.). Boston: Pearson.
Savva, S., Laminsos, D., & Kafatos, A. (2013). Predicting cardiometabolic risk: waist-to-height ratio or BMI. A meta-analysis. Diabetes, Metabolic Syndrome, and Obesity: Targets and Therapy, 403-419.