Patient Pre-Treatment Expectations Do Not Predict Cocaine Use Outcomes: Data From Four Clinical Trials.

BACKGROUND: There are very few data regarding the extent to which patients' initial expectations regarding treatment are associated with substance use treatment outcomes. OBJECTIVE: This study sought to determine how patients' treatment expectations were associated with treatment outcomes. METHODS: This study explored patient pre-treatment expectations and substance use treatment outcomes for 387 individuals participating in treatment for cocaine use within the United States (68.2% male, mean age 36 years old, 54.8% Caucasian). RESULTS: Participants' expectations regarding abstinence were not strongly associated with post-treatment or follow-up cocaine use outcome measures. There was a significant association between the expected timeframe of receiving a positive treatment effect (i.e., outcome efficiency expectations) and days of cocaine use at the 1-month follow-up point (F = 3.45, p =.009). Post-hoc comparisons revealed that participants that expected positive effects of treatment within 0-1 week reported fewer days of cocaine use than those that expected results in 1-2 months. Also, those that expected positive effects of treatment in 1-2 months reported more cocaine use than those who expected positive results within two weeks to one month. Further, there was a significant effect of outcome efficiency expectations on a proxy measure of achieving a good treatment outcome at the three-month follow-up point (F = 11.13, p =.025). CONCLUSIONS/IMPORTANCE: Results suggest that treatment outcomes are not associated with patients' treatment outcome expectations, but that some outcomes are associated with treatment outcome efficiency expectations.