Table 2.

Summary of Results from Adhesion Gradient Experiments

				Average number of neurites per device (standard error)
Channel width	Peptide	Condition	Number of devices (n)	Down	Up	Growth ratio (standard error)	p Value for growth ratio (versus controls)
3 mm	IKVAV	Control	7	13 (2)	14 (2)	1.10 (0.03)	N/A
		0–100	4	14 (1)	17 (2)	1.34 (0.18)	0.144
		0–50	5	17 (2)	18 (4)	1.08 (0.07)	0.687
	YIGSR	Control	8	13 (2)	13 (2)	1.11 (0.03)	N/A
		0–100	4	14 (2)	17 (2)	1.47 (0.15)	0.019*
		0–50	4	15 (2)	14 (2)	1.41 (0.07)	0.051
5 mm	IKVAV	Control	6	13 (2)	14 (2)	1.14 (0.04)	N/A
		0–100	5	16 (2)	15 (1)	1.14 (0.04)	0.954
		0–50	5	12 (1)	12 (2)	1.47 (0.21)	0.010*
		100–100	5	11 (1)	11 (2)	1.23 (0.13)	0.455
	YIGSR	Control	7	12 (1)	12 (1)	1.16 (0.05)	N/A
		0–100	5	12 (2	15 (2)	1.65 (0.28)	1.1e-4*
		0–50	5	15 (2)	14 (1)	1.18 (0.06)	0.754
		100–100	5	13 (2)	14 (1)	1.09 (0.03)	0.708
	YIGSR+IKVAV	Control	8	12 (4)	11 (4)	1.14 (0.02)	N/A
		0–100Y+50I	8	12 (4)	11 (4)	1.74 (0.14)	1.6e-7*

^*p<0.05.

Results are presented as the average value, with standard error of the mean in parentheses. For each condition, the number of neurites growing up the gradient versus down the gradient was compared with a paired t-test, and no significant differences were identified. The growth ratio was calculated as the average growth up the gradient (or in the longer direction for controls), divided by growth down the gradient (or in the shorter direction for controls). These values were compared with analysis of variance, followed by pair-wise comparisons against the appropriate controls with Fisher's LSD test.