Predictive validity of the Brazilian version of the Expected Treatment Outcome Scale in cocaine-dependent outpatients at a drug treatment referral center.
BACKGROUND
High dropout rates among patients under treatment for cocaine dependence have stimulated research into predictors of treatment outcome.


OBJECTIVE
To assess the predictive value of the Brazilian version of the Expected Treatment Outcome Scale.


METHODS
The original English version of the scale was translated and back-translated. A total of 210 subjects participating in a 10-week randomized double-blind clinical trial (nefazodone versus placebo) completed the questionnaire at their first appointment. Mean Expected Treatment Outcome Scale scores were compared with treatment outcomes.


RESULTS
There were ten subjects (5%) who failed to complete at least six items, and 37 (17.5%) failed to complete 1 to 3 items. The most frequently unanswered questions involved time estimates (treatment time and abstinence) and third-party judgments. The mean score was 34.4 (9.3) (median, 33.9). There were no differences in mean scores between subjects evaluated in the first to the fifth appointment 35.2 (9.3) or in the sixth to the eleventh appointment 35.2 (9.3) (p = 0.13); completing the treatment 33.8 (10.3) or not 34.6 (9.1) (p = 0.64); remaining abstinent for three weeks 34 (9.3) or not 34.8 (9.4) (p = 0.58), and medication compliance 33.9 (8.8) or noncompliance 35.3 (10.3) (p = 0.34). The ROC curve of Expected Treatment Outcome Scale scores, when dropout was defined as not appearing for all 11 appointments, was linear, with an area under the curve of .54 (range, .44-.64), suggesting that the scale is ineffective in discriminating between cases and noncases.


CONCLUSIONS
In this study, the Brazilian version of the Expected Treatment Outcome Scale was found to have no predictive value for treatment adherence and abstinence in cocaine-dependent subjects subjected to a standardized treatment protocol.
Dinis
Marcelle Maria Lobo
MM
Hospital Universitário Pedro Ernesto, Universidad Estadual do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Passos
Sonia Regina Lambert
SR
Camacho
Luiz Antonio Bastos
LA
D000293:Adolescent; D000328:Adult; D000368:Aged; D000553:Ambulatory Care; D001938:Brazil; D019970:Cocaine-Related Disorders / Q000523:psychology / Q000628:therapy*; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D010349:Patient Compliance; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D016896:Treatment Outcome