Table 3.

Mean RMS values with standard deviations (SD) for the postural stability trials during standing on a stable support surface (trials 1–3) and on “foam” (trials 7–9)

Trial	Healthy persons		Persons with LBP		F-value	P-value
	RMS (m)	SD	RMS (m)	SD
1	0.0088	0.0054	0.0054	0.0050	2.24	0.142
2	0.0082	0.0050	0.0062	0.0053	1.71	0.197
3	0.0072	0.0044	0.0093	0.0051	2.35	0.132
7	0.0075	0.0034	0.0087	0.0036	1.26	0.268
8	0.0087	0.0029	0.0105	0.0027	4.51	0.046
9	0.0083	0.0033	0.0152	0.0029	52.60	0.0001

Bold values indicate statistically significant differences