Table 3.

Characteristics at enrollment associated with number of return visits (N=12,388)

Characteristics	IRR of Return Visits (95% CI)	Adjusted IRR of Return Visits(95% CI)**
Predisposing
Female	0.93 (0.87–1.00)*
< Age 30	0.51 (0.46–0.55)*	0.19 (0.15–0.24)*
Homeless	0.99 (0.84–1.17)
High school degree/GED	0.99 (0.93–1.06)
Race
White	Ref
Black/African-American
Other
Marital Status
Single	Ref	Ref
Widowed/Separated/Divorced	1.13 (1.05–1.21)*	Ref
Married	0.87 (0.78–0.97)*	0.47 (0.33–0.68)*
Enabling
Same Zip Code as Enrollment Site	1.45 (1.36–1.55)*	4.16 (2.64–6.56)*
Employed	0.74 (0.68–0.81)*	0.46 (0.26–0.81)*
Need
Drug treatment (ever)	0.96 (0.89–1.04)
>20 years of injection drug use	1.42 (1.34–1.51)*	3.38 (2.48–4.61)*
>4 injections per day	1.01 (0.94–1.09)

^*significant at p < .05

^**GEE was used to account for possible clustering effects by site; the exchangeable correlation (rho) for this model was .03. The overdispersion parameter for this model was 2.68. The offset was one year for all participants.