Does substance abuse treatment make a difference for child welfare case outcomes? A statewide longitudinal analysis Beth L. Green a, ⁎ , Anna Rockhill b , Carrie Furrer c a NPC Research, 4380 SW Macadam Ave, Suite 530, Portland, OR, 97239, United States b Child Welfare Partnership, United States c NPC Research, United States Received 12 November 2005; received in revised form 1 August 2006; accepted 9 August 2006 Available online 30 November 2006 Abstract Although substance abuse is one of the primary reasons that parents become involved with the child welfare system, there is surprisingly little empirical research that examines the relationship of substance abuse treatment to child welfare outcomes. In this statewide longitudinal study of 1911 women who had children placed in substitute care, we examined the influence of three key factors in the treatment process on child welfare outcomes. Results indicated that when these women entered treatment more quickly, spent more time in treatment, or completed at least one treatment episode, their children spent fewer days in foster care and were more likely to be reunified with their parents. These findings were significant even controlling for families' levels of risk including treatment and child welfare history, substance abuse frequency and chronicity, and demographic risks. Implications of these findings for improvements in the way that treatment services are provided to women in the child welfare system are discussed. © 2006 Elsevier Ltd. All rights reserved. Keywords: Substance abuse; Child welfare system; Treatment services 1. Introduction Substance abuse has consistently been found to be one of the key family issues in a large number of child welfare cases. Although estimates range widely, at least 25% and as many as 80% of children in foster care have at least one parent with a substance abuse issue (Murphy et al., Children and Youth Services Review 29 (2007) 460 – 473 www.elsevier.com/locate/childyouth ⁎ Corresponding author. E-mail address: green@npcresearch.com (B.L. Green). 0190-7409/$ - see front matter © 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.childyouth.2006.08.006