Table 4. Decompression sickness (DCS) number, incidence and relative risk for SC HBG by exposure group (see text for explanation) .

Q = P√t	DCS/no DCS	DCS (%)	DCS/no DCS	DCS (%)	RR	p-value
	SC HBG = 1		SC HBG = 0
[0−150]	0/6	0	0/351	0	NA	-
[150−200]	3/28	10.7	1/169	0.6	17.8	0.01
[200−250]	6/56	10.7	4/224	1.8	6.0	0.007
[250−300]	5/45	11.1	3/115	2.6	4.3	0.05