Conclusions: The DR-LOC has shown to effectively translate generalized expectancies of control into a measure of control expectancies for drug-related situations, making it more sensitive for drug-dependent individuals than Rotter's I-E scale. Further research is needed to demonstrate its performance at discriminating between heterogeneous clinical groups such as between treatment-seeking versus non-treatment-seeking drug users.
(C) 2012 Lippincott Williams & Wilkins, Inc. (Source: Addictive Disorders and Their Treatment)

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