Table 3. The contact area and body pressure distribution parameters on the human-chair interface: backrest/seat.

	Index	Office chair	Bamboo sheet chair	Wooden chair	F	Sig
Backrest	St/cm2	314.96 ± 118.62a	325.55 ± 73.99a	182.22 ± 87.52b	16.88	0.00
	Sl/cm2	192.81 ± 89.49a	234.22 ± 55.80b	120.58 ± 63.03c	15.78	0.00
	Sm/cm2	81.430 ± 45.04a	52.96 ± 32.94b	32.90 ± 26.83b	11.17	0.00
	Sh/cm2	13.54 ± 12.00a	4.34 ± 5.95b	3.73 ± 5.67b	10.28	0.00
	Pressure exponent/kPa	4.32 ± 1.62a	2.68 ± 0.88b	2.85 ± 1.16b	12.42	0.00
	Maximal pressure/kPa	10.50 ± 3.88a	6.66 ± 2.05b	6.94 ± 2.58b	12.72	0.00
	Average pressure/kPa	3.43 ± 0.97a	2.42 ± 0.59b	2.53 ± 0.86b	10.79	0.00
Seat	St/cm2	1111.81 ± 136.75a	888.79 ± 124.87b	791.56 ± 103.01c	43.23	0.00
	Sl/cm2	418.79 ± 82.05a	324.33 ± 53.45b	278.24 ± 57.27c	28.72	0.00
	Sm/cm2	394.39 ± 98.99a	307.75 ± 90.31b	270.94 ± 82.61b	11.65	0.00
	Sh/cm2	268.17 ± 63.39a	232.17 ± 75.65b	224.15 ± 87.83b	2.27	0.00
	Pressure exponent/kPa	9.59 ± 1.94a	10.83 ± 1.76b	11.92 ± 2.03b	8.87	0.00
	Maximal pressure/kPa	23.08 ± 4.82a	26.26 ± 4.28b	28.91 ± 4.90c	9.35	0.00
	Average pressure/kPa	7.19 ± 1.19a	7.770 ± 1.30b	8.33 ± 1.41c	5.15	0.01

Notes.

St, Sl, Sm and Sh refer to total contact area of human-chair, contact area in low pressure threshold (from 0.67 kPa to 4.00 kPa), contact area in middle-to-high pressure threshold (from 4.00 kPa to 9.33 kPa) and contact area in high pressure threshold (over 9.33 kPa), respectively.

The different superscript indicates that there is significant difference (p < 0.05) between the two types. On the contrary, there is no significant difference.