Drug use-related outcomes
Building on Jacobson’s (2004) framework, this study focused on
several outcomes related to drug use and treatment use. The participants’
injection drug-related locus of control (LOC) was based on
a series of six yes/no questions created specifically for this study: It
is my own behavior, which determines whether I will inject drugs
in the next 6 months; No matter what I do, if I’m going to inject
drugs in the next 6 months, I will inject drugs in the next 6 months;
I’m in control of whether or not I will inject drugs in the next 6
months; If I take the right actions, I can avoid injecting drugs in the
next 6 months; I can change my drug use behaviors so that I do not
inject drugs in the next 6 months; and No matter what I do, I am
not likely to inject drugs in the next 6 months. The “no” responses
were coded as 0 and the “yes” responses were coded as 1 (question
2 was reverse coded). We then computed a summative score
ranging from 0 to 6 and dichotomized the sample into individuals
with internal LOC (score of 4 or higher) and those with external LOC
(score less than 4).
Since this was a cross-sectional study, we relied on participants’
self-reports in order to assess for the risk of future drug use. The
participants’ perceptions of the potential of injecting heroin in the
future were measured by two 5-point Likert questions: the chances
of injecting in the next six months; and how worried they were
about injecting in the next six months. Based on the distribution of
responses, the chances measure was dichotomized into “very high
chance” versus “medium/low/very low/no chance” groups while
the worried measure was dichotomized into “extremely/quite worried”
versus “somewhat/only a little/not at all worried” groups.
Treatment use was represented by two measures: (1) whether
the participant ever sought treatment (yes vs. no) and (2) whether
the participant ever received treatment (yes vs. no). Finally, the
location of last heroin purchase was a dichotomous measure, based
on whether the participants made their last heroin purchase inside
or outside the neighborhood