Table 1. Baseline demographic characteristics and recent injecting behaviors of hepatitis C virus (HCV) negative young injection drug users in San Francisco with ≥1 injecting partner (N = 448).

Demographic characteristics	N or Median	% or Interquartile Range (IQR)
Age in years (median; IQR)	24.0	21.4, 26.4
Female	131	29.2
Less than high school education	145	32.6
White	294	65.6
Homeless/marginally housed, prior 3 months	334	74.6
Ever incarcerated (jail or prison)	359	80.1
Incarcerated (jail or prison), prior 3 months	114	25.6
Traveled outside of San Francisco, prior 3 months	188	42.0
Participant HCV/HIV status
Self-reported HCV status (n = 386)*
Negative	234	60.6
Positive	4.0	1.0
Unknown	31	8.0
Never tested	115	29.8
Self-reported HIV status (n = 445)
Negative	319	71.7
Positive	10	2.2
Unknown	22	4.9
Never tested	69	15.5
Participant drug and alcohol use
Audit-C score, prior month (n = 360)#
Low risk	175	48.6
Hazardous	140	38.9
Probable dependent	45	12.5
Drank alcohol 21 or more days, prior month	93	20.8
Smoked crack cocaine, prior 3 months	247	55.3
Snorted or smoked methamphetamine, prior 3 months	295	65.9
Years since first injected, median (IQR)	3.8	1.7, 7.2
Number of days injected, prior 30 days, median (IQR)	25	10, 30
Injected every day, prior 30 days	171	38.2
Number of people with whom participant reported having injected with in the prior month; median (IQR)	4	2, 10
Participant recent injecting exposures: prior 3 months
Injected heroin (by itself or mixed with other drugs)	365	81.5
Injected methamphetamine	272	60.7
Injected powder cocaine	112	25.0
Injected crack cocaine	319	78.4
Obtained needles/syringes at syringe service program	349	78.1
Injected with the same needle/syringe >1 time	425	95.1
Any receptive needle sharing (yes)	135	30.3
Any shared ancillary equipment (yes)	276	61.7

* Participants who knew they were HCV viremic (RNA-positive) were screened out at baseline

# Sample size is lower as Audit C measures were added in 2006