Table 4.

Dependence and co-dependence rate of six substances. nic: nicotine; mj: marijuana; coc: cocaine; op: opiates; alc: alcohol; oth: other drugs. The percentage in the parenthesis is the dependence or co-dependence rate in the 3,627 unrelated subjects.

	Substance Dependence
	nic (%)	mj (%)	coc (%)	op (%)	alc (%)	oth (%)
nic	1625 (45)
mj	486 (13)	620 (17)
coc	686 (19)	464 (13)	937 (26)
op	203 (6)	145 (4)	217 (6)	258 (7)
alc	1154 (32)	577 (16)	820 (23)	238 (7)	1693 (47)
oth	332 (9)	258 (7)	335 (9)	168 (5)	406 (11)	432 (12)