METHOD: Substance dependent women on TANF (N=302) were recruited from local welfare offices in Essex County, NJ; assessed after screening; and randomly assigned to ICM or usual care (UC). Participants were re-assessed at 3, 9, 15, and 24 months. UC consisted of a health assessment at the local welfare office and referral to substance abuse treatment and TANF services. Clients in the experimental condition received ICM, a manual guided intervention that combined extensive outreach, assessment, and provision of services, in addition to the UC services. Appropriate to the longitudinal, repeated measures nature of the data, Generalized Estimating Equations (GEE) modeling was used to assess the predictive value of ICM in facilitating outpatient substance abuse treatment attendance and abstinence for women with high and low depressive symptoms (measured by the Beck's Depression Inventory-II). The data were modeled using Negative Binomial regression models with log link function, which provided the best model fit.
FINDINGS: When controlling for baseline differences, attendance rates for women with high depression in ICM were twice as high as those with low depression or those with high depression in UC through 24 months of follow-up (Incidence Rate Ratio, IRR = 2.78, 95% CI = 1.11-6.94). In addition, women with high depression in ICM demonstrated half as many drinks per drinking day as other women with high depression or those in UC (IRR = .515, 95% CI = 0.304-0.880). While intensity of drinking was found to be significant, neither of the frequency variables (number of days used alcohol or drugs) were found to be significant.
CONCLUSION: Findings presented here suggest that ICM is a promising intervention for managing the chronic nature of co-morbid depression and substance dependence for TANF women, improving both attendance rates and reducing intensity of alcohol use. Findings also point to the unexpected vulnerability of women with low depression who did not benefit from ICM as effectively as women with high depression.