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Updated: Oct 20, 2026

A Protocol for Measuring Cue Reactivity in a Rat Model of Cocaine Use Disorder
Published on: June 18, 2018
Predictors of change in frequency of crack cocaine use in a street-recruited sample
S Deren1, M Beardsley, S Tortu
1National Development and Research Institutes, Inc., New York, NY 10048, USA. sherry.deren.@ndri.org
Abstract:
Crack cocaine users are at high risk for HIV, with higher frequency crack users engaging in higher rates of HIV-related sexual risk behaviors. This study will assess the variables impacting changes in crack use frequency. Out-of-treatment crack users were street recruited in East Harlem, NY. Subjects (n = 727) were 33% female, 91% minority, and 28% reported recent drug injecting. Baseline and 6-month follow-up interviews were administered. There was a significant reduction in crack use over time (p < .0001). Subjects were categorized according to five groups, based on their change in level of crack use between the two interviews, to predict those who stopped, maintained, or changed their level of use. Discriminant analyses identified six variables as the best predictors of the five groups, including having been in drug treatment since baseline and having been a drug injector (both related to reduced levels of crack use). The overall reduction in crack use for the sample masked the fact that important subgroups remained at high use levels or increased their use. The identification of subgroups who may be most resistant to reducing drug use can be helpful in developing more effective interventions.
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