Contingency management for patients with dual disorders in intensive outpatient treatment for addiction.

OBJECTIVE: This quality improvement program evaluation investigated the effectiveness of contingency management for improving retention in treatment and positive outcomes among patients with dual disorders in intensive outpatient treatment for addiction.
METHODS: The effect of contingency management was explored among a group of 160 patients exposed to contingency management (n = 88) and not exposed to contingency management (no contingency management, n = 72) in a six-week partial hospitalization program. Patients referred to the partial hospitalization program for treatment of substance use and comorbid psychiatric disorders received diagnoses from psychiatrists and specialist clinicians according to the Diagnostic and Statistical Manual of the American Psychiatric Association. A unique application of the contingency management "fishbowl" method was used to improve the consistency of attendance at treatment sessions, which patients attended 5 days a week. Days attending treatment and drug-free days were the main outcome variables. Other outcomes of interest were depression, anxiety and psychological stress, coping ability, and intensity of drug cravings.
RESULTS: Patients in the contingency management group attended more treatment days compared to patients in the no contingency management group; M = 16.2 days (SD = 10.0) versus M = 9.9 days (SD = 8.5), respectively; t = 4.2, df = 158, p <.001. No difference was found between the treatment groups on number of drug-free days. Psychological stress and drug craving were inversely associated with drug-free days in bivariate testing (r = -.18, p <.02; r = -.31, p <.001, respectively). Treatment days attended and drug craving were associated with drug-free days in multivariate testing (B =.05, SE =.01, β =.39, t = 4.9, p <.001; B = -.47; SE =.12, β = -.30, t = -3.9, p <.001, respectively; Adj. R(2) =.21). Days attending treatment partially mediated the relationship between exposure to contingency management and self-reported drug-free days.
CONCLUSIONS: Contingency management is a valuable adjunct for increasing retention in treatment among patients with dual disorders in partial hospitalization treatment. Exposure to contingency management increases retention in treatment, which in turn contributes to increased drug-free days. Interventions for coping with psychological stress and drug cravings should be emphasized in intensive dual diagnosis group therapy.