Implementing Behavioral Intervention Components in a Cost-Effective Manner: Analysis of the Incredible Years Program.

Abstract Multi-component interventions for conduct disorder target several contexts of a child's life (e.g., both home and school environments) and are generally more effective than single-component behavioral interventions. Whether the multi-component approach is cost-effective remains an unanswered question. This article analyzes two decades of data from the Incredible Years (IY) Series to examine the cost-effectiveness of delivering multiple, stacked intervention components versus a single-component delivery approach. Cost-effectiveness analysis (CEA) provides decision makers with important economic information that can be used to aid in the selection of a program delivery format from one of several competing approaches. CEA concepts, including explicit budget constraints and strict dominance, are demonstrated using IY data; guidelines for interpreting CEA results are provided. Our analyses suggest that combining intervention components is a cost-effective approach to treating behavioral problems in a clinic-based youth population. Keywords: cost-effectiveness, multi-component interventions, Incredible Years Series, conduct disorder. ********** Conduct disorder (CD) is among the most common emotional and behavioral disorders affecting youth (Institute of Medicine, 1989), occurring in an estimated 10 percent of preschool and early-school-age children (Institute of Medicine, 1989; Webster-Stratton & Reid, 2003). Children with CD often engage in a variety of behaviors that are detrimental to themselves, their families, and society (Institute of Medicine, 1989; Webster-Stratton & Reid, 2003). Youth diagnosed with CD exhibit persistent behaviors consistent with three or more of the following four behavioral categories: aggression toward people or animals; property destruction; deceitfulness or theft; and serious rule violations (DSM-IV, 1994). These children frequently lack critical social and self-regulation skills necessary for making friends, and, as a result, often endure peer rejection and isolation from an early age (Kaiser & Hester, 1997; Miller-Johnson, Coie, Maumary-Gremaud, Bierman, & CPPRG, 2002). CD puts youth at risk for other costly outcomes such as weapon use, alcohol use, and other drug use and increases the likelihood of teenage pregnancy, dropping out of school, and police contact (Robins and Price, 1991; Achenbach, Howell, McConaughy, & Stanger, 1998; Bardone, Moffitt, Caspi, Dickson, Stanton, & Silva, 1998; Scott, 1998). Scott, Knapp, Henderson, and Maughan (2001) found evidence of a linear relationship between severity of conduct problems and societal costs; children with conduct problems (but who did not meet diagnostic criteria for CD) and children diagnosed with CD generated societal costs three and ten times greater than children with no conduct problems, respectively. Children with CD often become involved with public, child-serving systems, such as juvenile justice. This involvement creates juvenile court costs, incarceration costs, costs of lost productivity due to incarceration, and victim costs (both tangible and intangible) all borne by society (Cohen, 1998). Cohen (1998) estimates that one life of crime results in societal costs ranging from $1.3 to $1.5 million. Research suggests that early intervention is most effective, especially for those at greatest risk. Although the incidence of CD is higher among adolescents (Searight, Rottnek, & Abby, 2001), a small minority of young children begin to display conduct disorder symptoms as early as preschool age (Moffitt, 1993). Without intervention, childhood-onset CD generally results in bleaker trajectories than adolescent-onset CD (Searight et al., 2001). Compared with their peers, children identified in kindergarten as high-risk for behavioral problems are more likely to be placed on medication, to repeat a grade, to receive mental health services, and to come in contact with police (Jones, Dodge, Foster, Nix, & CPPRG, 2002). …