Clinical study to evaluate the safety and effectiveness of the Aesculap Activ-L™ artificial disc in the treatment of degenerative disc disease

Table 2 Power Analysis results using PASS 2005 Software (NCSS Kayesville, Utah) PASS 2005 Power Analysis Results.

	Sample Size Group 1	Sample Size Group 2	Group 1 or Treatment	Group 2 or Control	Diff if H0	Diff if H1
Power	N1	N2	P1.1	P2	D0	D1	Target Alpha	Beta
0.8000	178	89	0.6771	0.5000	0.0000	0.1771	0.0500	0.2000
0.8000	178	89	0.7227	0.5500	0.0000	0.1727	0.0500	0.2000
0.8000	178	89	0.7665	0.6000	0.0000	0.1665	0.0500	0.2000
0.8000	178	89	0.8086	0.6500	0.0000	0.1586	0.0500	0.2000
0.8000	178	89	0.8487	0.7000	0.0000	0.1487	0.0500	0.2000
0.8000	178	89	0.8865	0.7500	0.0000	0.1365	0.0500	0.2000
0.8000	178	89	0.9218	0.8000	0.0000	0.1218	0.0500	0.2000

Two Independent Proportions (Null Case) Power Analysis Numeric Results of Tests Based on the Difference: P1 - P2 H0: P1-P2 = 0. H1: P1-P2 = D1 <> 0. Test Statistic: Z test with pooled variance

ISSN: 1471-2482