Ten patients with advanced diabetic nephropathy (kidney complications of diabetes) were treated with captopril over an 8-week period. Urinary protein was measured before and after drug therapy, with the results listed below.

What's the appropriate statistical procedure to test whether mean urinary protein has changed over the 8-week period?

Patient Raw scale urinary protein ln scale urinary protein

Before After Before After

1 25.6 10.1 3.24 2.31

2 17.0 5.7 2.83 1.74

3 16.0 5.6 2.77 1.72

4 10.4 3.4 2.34 1.22

5 8.2 6.5 2.10 1.87

6 7.9 0.7 2.07 -0.36

7 5.8 6.1 1.76 1.81

8 5.4 4.7 1.69 1.55

9 5.1 2.0 1.63 0.69

10 4.7 2.9 1.55 1.06