 0.0000$                          *p* = 0.0000            *p* = 0.0000              *p* = 0.0000   Injection-drug use 0   $\hat{\tau} = 0.0000$   $\hat{\tau} = - 0.0000$   $\hat{\tau} = 0.0000$                          *p* = 0.0000            *p* = 0.0000              *p* = 0.0000   Injection-drug use 0   $\hat{\tau} = 0.0000$   $\hat{\tau} = 