During the last thirty years, there have been many studies that have detailed the needs and problems of children in foster care. Although studies have differed in the methodologies employed and the factors considered, the findings have generally been consistent. Children in foster care tend to obtain lower scores on most measures of psychosocial and physical well-being compared with normative populations of a similar age. Within foster care populations, there is a higher prevalence of disabilities and developmental difficulties (Coyne and Brown 1986; Hochstadt et al. 1987; Reed 1997); poorer educational outcomes (Blome 1997; Dubowitz et al. 1994; Heath, Colton and Aldgate 1994), conduct disorder and offending (Reid, Kagan and Schlosberg 1988); psychological problems such as hyperactivity, depression and anxiety, and difficulties in socialization (Klee and Halfon 1987). A substantial percentage of foster children are victims of abuse (Benedict et al. 1989; Courtney 1994; Hochstadt et al. 1987), and many come from family backgrounds with histories of intergenerational abuse, where parents have limited resources, parenting skills and social networks (Leifer, Shapiro and Kassem 1993). Given their background problems, it is not surprising that foster children are at significant disadvantage compared with other children, and that normative comparisons must be undertaken with considerable caution. Accordingly, a preferred approach, and one adopted in our own project, is to examine only within-sample changes; namely, how foster children fare over time relative to their own individual standards and competencies.
Although the central aim of much foster care research has been to determine how variations in placement experiences influence different children, much of it has been limited by a failure to appreciate the complex interaction between child and placement characteristics (Courtney 1993; Farmer 1996). Many of these problems are attributable not so much to any lack of understanding of the issues involved but to unsatisfactory methodological designs. As indicated in Chapter 4, the most significant limitation of these designs, and of cross-sectional designs in general, is that they tend to