Abbott Proclaim 3660 Clinician Manual page 55

In addition to demonstrating non-inferiority, superiority was also shown. The following table
contains the results of testing the superiority hypothesis for burst over tonic stimulation. The
difference in the overall VAS score between burst and tonic stimulation is -5 points, with a 95%
UCB of -1.14, which is less than 0 and results in a rejection of the hypothesis that burst
stimulation is not superior to tonic stimulation (p=0.017). Therefore, the results demonstrate that
burst stimulation is superior to tonic stimulation.
Table 29. Superiority of overall VAS score with burst over tonic
Randomization
Burst
Mean ± SD (N)
Minimum, Median, Maximum
Tonic
Mean ± SD (N)
Minimum, Median, Maximum
Burst-Tonic
Mean ± SD (N)
Minimum, Median, Maximum
Burst-Tonic Average ± Pooled SD
Across Arms
95% UCB on Difference (Burst-Tonic)
Superiority Margin
p
-value for Superiority Test
Endpoint Met?
t
95% UCB and p-value for superiority are based on a t-distribution with n
freedom, where n and n
1
The following figure presents the overall VAS scores by visit and by stimulation mode. The graph
on the left shows that both randomization groups had high overall VAS scores at baseline and, at
week 12, both stimulation modes reduced the overall VAS score as expected since all subjects
were known responders to tonic stimulation during the stimulation trial period). The graph on the
right shows these same data by stimulation method. The figure shows a large reduction in overall
VAS score from baseline with burst stimulation and less reduction in VAS during tonic stimulation.
42.7±26.1 (45)
0.9, 41.1, 100.0
46.3±22.8 (45)
1.0, 49.3, 88.1
-3.6±26.3 (45)
-64.6, -3.7, 79.0 -70.4, -2.6, 48.4
are the number of subjects in each arm.
2
Arm 1: Arm 2:
tonic/burst burst/tonic
44.2±25.3 (55)
0.0, 45.1, 98.1
50.7±24.8 (55)
0.0, 49.3, 98.7
-6.5±21.0 (55)
-5.1±11.8
-1.14
0.017
51
Pooled
43.5±25.6
(100)
—
48.7±23.9
(100)
—
—
—
t
0
t
Yes
+n -2 degrees of
1 2