Table 5.

Comparison of CSAs at the 8-points among the two most frequent positive sites and the negative site in the inching test

	none (n = 119)	i4-i3 (n = 37)	i3-i2 (n = 55)
i4	13.9 ± 4.8(7-40.8)	19.5 ± 6.9 (9-37)*	19.0 ± 6.9 (8-41)*
i3	13.6 ± 4.8 (8-40.8)	17.4 ± 5.0 (8-32) *	17.9 ± 6.3 (8-42)*
i2	12.0 ± 3.1 (8-29)	12.4 ± 3.1 (6-19)	13.2 ± 3.4 (8-25)
i1	12.4 ± 4.1 (7-34.4)	13.6 ± 4.5 (7-31)	14.6 ± 4.3 (7.4-25)*
w	12.5 ± 4.0 (7-31)	14.5 ± 4.6 (7-27)	15.6 ± 4.9 (7-33)*
o1	11.3 ± 2.8 (6-20.7)	13.1 ± 2.9 (9-20)	13.6 ± 3.6 (8-26)*
o2	11.0 ± 2.4 (6-18.5)	12.2 ± 2.4 (8-18)	12.8 ± 2.7 (8-21.3)*
o3	10.5 ± 2.6 (5-19)	10.5 ± 2.3 (6-16)	11.8 ± 2.4 (8-19)*

Note: CSA, cross-section area; none, no conductive delay >0.4 ms in median inching test in centimeter across the carpal tunnel; i4-i3, conductive delay >0.4 ms in inching test between 4 cm and 3 cm distal to the wrist crease; i3-i2, conductive delay >0.4 ms in inching test between 3 cm and 2 cm distal to the wrist crease

Markers of the 8-point: i4, i3, i2, i1, w, o1, o2, and o3

i4-i3 and i3-i2: the difference of latency measured between locations of i4 and i3, and i3 and i2 in the inching test

Unit of CSA = mm²

*p < 0.05 in comparing the two most frequent positive sites and the negative one in inching test using analysis of variance (ANOVA) followed by Scheffe's multiple comparison procedure