Question

The subjects of a study by Dugoff et al. (A-5) were 10 obstetrics and gynecology interns at the

University of Colorado Health Sciences Center. The researchers wanted to assess competence in

performing clinical breast examinations. One of the baseline measurements was the number of such

examinations performed. The following data give the number of breast examinations performed for

this sample of 10 interns.

Intern Number No. of Breast Exams Performed

1 30

2 40

3 8

4 20

5 26

6 35

7 35

8 20

9 25

10 20

Answer 1

$\bar x=25.9,s=9.4687, n=10.$

$95\%CI=(\bar x-t_{0.025,n-1}\frac{s}{\sqrt{n}},\bar x+t_{0.025,n-1}\frac{s}{\sqrt{n}})=$

$=(25.9-2.2622\frac{9.4687}{\sqrt{10}},25.9+2.2622\frac{9.4687}{\sqrt{10}})=(19.1264,32.6736)$.