Question

Doctors developed an intensive intervention program for obese patients with heart disease. A random sample of subjects with a BMI of 30 kg/m2 or more, with heart disease, were assigned to a three-month lifestyle change of diet and exercise. Patients' left ventricle ejection fraction (LVEF) was measured before and after the intervention. A normal heart's ejection fraction may be between 50 and 70 percent, higher numbers indicate a healthier heart. Assume LVEF's are normally distributed. Before: 58, 44, 53, 54, 49, 45, 57, 65, 43, 46. After: 59, 57, 62, 59, 60, 57, 48, 49, 56, 60, 56, 61. For this problem, d = before - after, where the first data set represents 'before' and the second data set represents 'after'. Find the 95

Answer 1

To evaluate the effect of a dietary and exercise intervention on LVEF in obese patients with heart disease, differences in pre- and post-intervention LVEF values must be calculated and analyzed statistically, typically via a paired t-test, to derive conclusions at a
`95`% confidence level.

Step-by-step explanation:

Doctors developed an intensive intervention program for obese patients with heart disease aimed at lifestyle changes to improve cardiac function, specifically the left ventricle ejection fraction (LVEF). The LVEF is a key indicator of heart health, denoting the percentage of blood pumped out of the left ventricle with each contraction. To analyze the effectiveness of this intervention, we calculate the differences in LVEF 'before' and 'after' the program.

The provided LVEF values 'before' and 'after' need to be paired correctly for each patient to find d = before - after. Once we have the differences, we can apply statistical analysis (e.g., a paired t-test) to determine the impact of the program with a
`95`% confidence interval.