Between-day reliability of centre of pressure measures for balance assessment in hemiplegic stroke patients

Table 1 Descriptive data of CoP-based variables and characterization of the random error distribution

CoP-based variables	EO/EC	Session 1	Session 2	d(95% CI)	r	P-values
		Mean ± SD	Mean ± SD
VEL (mm.s^-1)	EO	14.8 ± 5.2	15.0 ± 6.7	0.1 (-1.2 to 1.5)	0.15	0.54
	EC	21.3 ± 11.3	21.4 ± 13.4	0.1 (-2.0 to 2.2)	0.34	0.15
SD_VEL (mm.s^-1)	EO	37.7 ± 12.3	37.8 ± 13.5	0.1 (-2.6 to 2.9)	0.10	0.66
	EC	38.1 ± 11.6	38.1 ± 12.8	0.0 (-2.7 to 2.7)	0.25	0.29
VEL_ML (mm.s^-1)	EO	7.6 ± 3.1	7.6 ± 4.0	0.0 (-0.8 to 0.8)	0.27	0.26
	EC	10.7 ± 5.8	10.6 ± 7.0	-0.1 (-1.3 to 1.1)	0.32	0.17
VEL_AP (mm.s^-1)	EO	10.1 ± 3.7	10.3 ± 4.7	0.3 (-0.8 to 1.4)	0.21	0.38
	EC	15.1 ± 8.6	14.8 ± 8.4	-0.3 (-2.0 to 1.3)	0.40	0.08
CE_AREA (mm²)	EO	438.3 ± 229.2	449.5 ± 377.8	11.2 (-188.6 to 140.9)	0.52	0.02*
	EC	558.6 ± 324.0	541.2 ± 431.5	-17.4 (-115.5 to 80.7)	0.56	0.01*
CoP_ML (mm)	EO	10.7 ± 9.9	13.8 ± 9.6	3.1 (-0.8 to 7.0)	0.05	0.82
	EC	14.1 ± 11.6	14.7 ± 9.9	0.5 (-4.3 to 5.3)	0.03	0.92

For each of the six CoP-based variables, mean ± standard deviation in session 1 and 2, and mean difference between the 2 test sessions (d) with its 95% confidence interval (95% CI) are reported in eyes open (EO) and eyes closed (EC) conditions. The detection of a possible heteroscedasticity of the random error distribution was done with calculation of Pearson’s correlation coefficient (r) between absolute individual test-retest differences and individual means of the two sessions. Significant p-values (p < 0.05) are indicated with an asterisk.

ISSN: 1743-0003