- Impacts were examined separately for the young children in the COS sample who, as of study entry, were at high risk or at low risk for poor development. Few impacts were found within these subgroups. Among these, impacts on children at higher risk were small, and in two of the three sites tended to be favorable for education-focused programs and unfavorable for employment-focused programs; impacts on children at lower risk were larger, tended to be unfavorable, did not tend to vary by program approach, and were clustered in three programs. This type of subgroup analysis was not conducted for school-age children across all sites.
In subgroup analyses examining child impacts for COS sample members, four subgroup divisions were defined, based on family baseline characteristics, that past research has suggested contain a higher-than-average proportion of children at risk for poor development. These overlapping subgroups included families with three children or more or at least two children born less than two years apart (the sibling configuration risk subgroup); families in which the mother, at baseline, did not have a high school diploma or GED or had low scores on reading or math tests (the educational risk subgroup); families in which the mother, at baseline, had received at least five years of welfare, reported at least four barriers to employment, or had never worked full time for six months or more for the same employer (the work risk subgroup); and families in which the mother, at baseline, reported symptoms of depression and a lack of control over her own life (the maternal psychological well-being risk subgroup). Within the COS control group, families who met the criteria of any of these four subgroups had children who, as of the two-year follow-up point, were generally not developing as well as children in families who did not meet these criteria.
Prior research, however, has suggested that the accumulation of risk may be more important than any particular risk factor for children's development. While a child may be able to overcome a single risk factor, the accumulation of risk may "tip the scales" against a child, and result in unfavorable child outcomes. For the COS subgroup analysis, families who met the criteria of no subgroup or only one subgroup were considered to be in the lower cumulative risk subgroup; families who met the criteria of two, three, or all four of the subgroups were considered to be in the higher cumulative risk subgroup. Thus, all families were in one of these two subgroups.
Relatively few young child impacts were found for each of the four defined overlapping subgroups and for the cumulative risk subgroups. The impacts on focal children at higher risk for poor development were small, but in two of the three sites tended to be favorable for education-focused programs and unfavorable for employment-focused programs. The impacts on focal children at lower risk for poor development were larger, tended to be unfavorable, and did not tend to vary by program approach.(28) The unfavorable impacts for focal children at lower risk were clustered in the Grand Rapids LFA program and in both of the Riverside programs. As noted earlier, this type of subgroup analysis was not conducted for school-age children across all evaluation sites.