Table 1.

Baseline characteristics of the 1139 male PWID participants, by HIV status.

		HIV Negative		HIV Positive
		N=774 (68.0%)		N=365 (32.0%)
		%	95% CI	%	95% CI
Size of sharing network*
	1	44.3	(40.8–47.8)	46.3	(41.2–51.4)
	2–3	49.9	(46.3–53.4)	48.5	(43.4–53.6)
	4 or more	1.8	(0.9–2.7)	1.1	(0–2.2)
Demographics
	Age, in years (median, IQR)	35	(29–40)	34	(30–38)
	Years of education (median, IQR)	9	(7–12)	9.0	(7–11)
	Stable sexual partner†	48.3	(44.8–51.8)	43.6	(38.5–48.6)
	Employed‡	91.9	(89.9–93.8)	84.9	(81.3–88.6)
	Income per month in millions of dong (median, IQR)	2	(1.5–2.5)	1.5	(1.0–2.5)
Drug use related behaviors
	Injected daily, past 3 months§	42.2	(38.8–45.7)	51.2	(46.1–56.4)
	Duration of drug use, in years (median, IQR)‖	12	(7–18)	12	(9–18)
	Ever in drug treatment in lifetime	29.8	(26.6–33.1)	30.7	(26–35.4)
	Ever overdosed on drugs in lifetime	19.3	(16.5–22)	21.1	(16.9–25.3)
Other reported histories
	Ever arrested in lifetime	41.2	(37.7–44.7)	44.4	(39.3–49.5)
	Ever in prison in lifetime¶	35.4	(32–38.8)	36.4	(31.5–41.4)
	Ever spent a night in street, in a park, alley, or abandoned building in last 3 months	20	(17.2–22.8)	16.4	(12.6–20.2)
	Had any unprotected sex, past 3 months#	80.9	(78.1–83.6)	69	(64.3–73.8)
HIV related factors
	Knew own HIV status at baseline	16	(13.4–18.6)	20.5	(16.4–24.7)
	CD4 cell count (median, IQR)	--		234	(125–372)

^*535 (32.0%) of participants reported not sharing with any partners in the past 3 months, and 46 (4.0%) were missing network information.

^†A "stable partner" was defined as someone to whom the participant is married or cohabitating.

^‡1 person was missing injection frequency information.

^§7 people were missing information on duration of injection drug use.

^‖1 person was missing information on past incarceration.

^¶Employment either full or part time.

^#Unprotected sex was assessed for partners of either sex; 28 (2.4%) people were missing this information.