Table 2.

Bivariate factors associated with initiating someone into drug injection in the last 12 months among people who inject drugs in Los Angeles and San Francisco, California (N=605)

Variable	Initiation in last 12 mos (n=44) n (%)	No initiation in last 12 mos (n=561) n (%)	p=
Recruitment City			0.04
Los Angeles	29 (66%)	279 (50%)
San Francisco	15 (34%)	282 (50%)
Age cohorts (born in)			0.001
Pre-1960s	15 (34%)	250 (45%)
1960s	10 (23%)	172 (31%)
1970s	5 (11%)	78 (14%)
1980s or later	14 (32%)	61 (11%)
US Born - Yes	39 (89%)	538 (96%)	0.05
Income source, last 30 days
Spouse you live with	8 (18%)	36 (6%)	0.01
Illegal or possibly illegal source	25 (57%)	210 (37%)	0.02
Panhandling	20 (46%)	149 (27%)	0.01
Steady sex partner is a PWID – Yes	21 (48%)	151 (27%)	0.005
Paying sex partner in the last 6 months – Yes	11 (25%)	70 (13%)	0.04
Paying sex partner is a PWID – Yes	8 (18%)	44 (8%)	0.04
Non-injection drug use, last 30 days
Powder cocaine	12 (27%)	42 (8%)	<0.0001
Marijuana	32 (73%)	302 (54%)	0.02
Injected 2 or more drugs, last 30 days – Yes	25 (57%)	218 (39%)	0.03
Injection frequency, last 30 days			0.02
Less than once a day	13 (30%)	285 (51%)
Once or twice a day	18 (41%)	151 (26%)
Three times or more a day	13 (30%)	125 (21%)
Years of injection			0.005
<10	15 (35%)	76 (14%)
10–19	4 (9%)	94 (17%)
20 or more	24 (56%)	372 (69%)
Any public injection, last 30 days – Yes	33 (75%)	285 (51%)	0.003
Injected other person in last 30 days – Yes	28 (64%)	146 (26%)	<0.0001
Injected by another person, last 30 days – Yes	17 (39%)	124 (22%)	0.02
Inject in front of non-injectors in the last 12 months			<0.0001
Yes	30 (68%)	203 (36%)
Ever described injection to non-injector – Yes	33 (75%)	195 (35%)	<0.0001
Likelihood of initiating in the future			<0.0001
Yes	29 (66%)	110 (20%)