[Situation determinants of heroin consumption in opiate-dependent subjects: a psychometric approach]

Evaluation of the situations related to heroin-taking, and the consequent delimitation and characterization of the patient's drug-taking pattern, should be one of the first stages in the design of an individualized treatment in the context of a cognitive-behavioural therapeutic approach. The Inventory of Drug-Taking Situations (Heroin) (IDTS[H]; Annis y Martin, 1985) was administered to a sample of 124 opiate dependent patients in order to study its reliability and factor structure. An Alpha reliability coefficient of .93 was obtained. A principal component analysis of the measure revealed a five-component solution which accounted for 50.6% of the variance. Nevertheless, a confirmatory factor analysis of the self-report showed that the original eight-factor model provides an acceptable fit to the data. Lastly, the frequency at which each of the eight original IDTS(H) subscales appeared as the highest risk situation in the profile was calculated, showing the predominance of Negative Emotional States (35%) and Social Pressure to Use (18%) as the two most important high-risk situations. Theoretical and clinical implications of the results are discussed.