TABLE 3—

Correlates of Age at Initiation of Injection Drug Use Among 2143 Young Adult Injection Drug Users: 5 US Cities, 1997–1999

Characteristic	Mean Age at Initiation, y (SD)	Pa
Site
Baltimore	22.9 (3.9)	<.001b
Chicago	20.5 (3.9)
Los Angeles	17.7 (3.9)
New Orleans	17.6 (3.8)
New York: Harlem	20.1 (4.0)
New York: Lower East Side	18.3 (3.9)
Demographics
Female	20.0 (4.4)	<.001
Male	19.2 (4.1)
Mean age (SE)	19.5 (4.2)
Race/ethnicity
African American	21.8 (4.6)	<.001b
White	18.6 (3.7)
Hispanic	20.4 (4.2)
Other/mixed	18.0 (4.2)
Recent homelessness	18.4 (4.0)	<.001
Foster home/orphanage	17.9 (4.4)	<.001
High school or general equivalency diploma	19.9 (4.1)	<.001
Gay/lesbian/bisexual	18.4 (4.1)	<.001
HIV+	20.1 (5.1)	.17
Injects daily	19.5 (4.3)	.99
Sexual abuse history
Age at 1st forced sex		<.001b
Never	19.7 (4.2)
< 13	17.7 (4.8)
13–17	18.8 (4.1)
≥18	20.9 (3.9)

^aMantel–Haenszel P values unless indicated otherwise.

^bAnalysis of variance P value.