TABLE 1.
Patterns of Participation of Original Intervention and Comparison Groups in the CLS
| Study category | Total Sample |
Preschool Intervention Group* |
Comparison Group* |
|---|---|---|---|
| Program Participants’ Characteristics at Start of Study** | |||
| Original Sample | 1539 | 989 | 550 |
| No. of cases with preschool participation | 1073 | 989 | 84 |
| No. of cases with CPC preschool | 989 | 989 | 0 |
| Years in CPC preschool (0–2) | - | 1.55 | 0.0 |
| No. of cases with Head Start preschool | 85 | 1 | 84 |
| No. of cases with kindergarten participation | 1539 | 989 | 550 |
| No. of cases with CPC participation | 989 | 989 | 0 |
| Full-day kindergarten, % | - | 59.9 | 100.0 |
| No. of cases with CPC school-age participation | 850 | 684 | 166 |
| Years of school-age program (0–3) | - | 1.43 | 0.68 |
| School-age participation, % | - | 69.2 | 30.2 |
| No. of cases with CPC extended intervention (4–6y) | 553 | 553 | 0 |
| Extended participation, % | - | 55.9 | 0.0 |
| Total years of CPC program (0–6) | - | 3.95 | 0.68 |
| No. of cases with no CPC participation | 384 | 0 | 384 |
| No. of Lost cases in Post-program Years | |||
| Moved*** | |||
| From ages 6–10y | 69 | 41 | 28 |
| After age 10y | 52 | 30 | 22 |
| Other | 11 | 4 | 7 |
| Child death | 18 | 12 | 6 |
| Follow-up Study Characteristics of Participants at Age 24–26, No. of cases with data | |||
| Educational attainment | 1373 | 893 | 480 |
| Arrest and incarceration | 1473 | 523 | 950 |
| Educational attainment and arrest and incarceration | 1364 | 887 | 477 |
| Substance misuse | 1473 | 950 | 523 |
| Depression | 1134 | 744 | 390 |
| One or more adult outcomes | 1445 | 936 | 509 |
Cases for program participation cover the 6-year period (1983–1989) that defines enrollment in the CPC intervention.
The CPC preschool comparison group participated in a full-day kindergarten program, and 84 had Head Start preschool. 176 cases in the preschool comparison group were eligible to receive limited services in the CPC kindergarten but enrolled in different classrooms. They are not part of the original CPC intervention group. Some cases in the comparison group participated in the school-age program because it was open to any child enrolled in elementary school from first to third grade. Fifteen children in the CPC intervention group enrolled in the alternative full-day kindergarten.
These categories account for attrition from the original study sample of 1,539. Cases were lost during post-program years because they moved from Chicago and could not be located, were deceased, or either did not have sufficient identifying information to track, refused to participate or were incarcerated (other). At age 24, the total number of deceased cases in the study was 41.