Study 1
Redmond and colleagues (1999) examined the long-term parenting outcomes of Guiding Good Choices (GGC), which was previously called Preparing for the Drug-Free Years. The original evaluation conducted by Spoth, Redmond, and Shin (1998) examined effects immediately postintervention; this 1999 study examined effects 1 year following the original posttest. In the original study, schools were selected on the basis of free-lunch-program eligibility and community size (population of 8,500 or fewer). Schools were assigned using a randomized block design, wherein blocks were formed on the basis of school size and the proportion of students residing in low-income neighborhoods. Within blocks, schools were assigned to GGC (n = 221 families), a second intervention group (Iowa Strengthening Families Program, n = 238 families) or a minimal contact control group (n = 208 families). At the 1-year follow up, the final sample consisted of GGC (n = 124 families), Iowa Strengthening Families Program (n = 141), and a minimal contact control group (n = 139). The CrimeSolutions review of this study focused on the comparison between the GGC group and the contact control group.
Participants were families of sixth graders enrolled in 33 rural schools in 19 contiguous counties in a midwestern state. The two groups were similar across sociodemographic characteristics at pretest, although the average number of years of education was greater for study participants (0.7 years more) than for the comparison group. The sample that completed both pretests and posttests was composed primarily of families that were dual-parent (85.0 percent) and white (98.6 percent). In 53 percent of the families, the target child for the intervention was female. The mean age of the sample was 11.3 years.
Study measures included parent-child affective quality, general child management, and intervention-targeted parenting behaviors (including substance use rules and consequences, anger management, and involving child in family activities), and were constructed from self-report items and observational ratings. The original analysis incorporated three waves of data collected over a 2.5-year period. This study included parenting outcomes 1 year following posttest. Intervention effects were examined through structural equation modeling of covariance matrices using maximum likelihood estimation. No subgroup analyses were conducted.
Study 2
Spoth and colleagues (2009) used the same sample as the original study by Spoth, Redmond, and Shin (1998) to assess the long-term, 10-year impact of the GGC program on the initiation of substance use (alcohol or tobacco) and on the progression from one status to another (e.g., from no-use to alcohol-only use). The 10-year follow-up period allowed the researchers to follow participants into young adulthood, and data were collected at seven points in time over that period.
The study used four measures to assess young adult substance use: frequency of drunkenness, alcohol-related problems, use of cigarettes, and use of illicit drugs. A fifth measure, for polysubstance use, was developed by dichotomizing answers for the previous measures and compiling them.
The primary analysis used an indirect effects model, which was designed to address issues related to the long follow-up period. The model compares case rates in the treatment and control conditions, which yields relative reduction rates—that is, the proportion of control condition cases that would have been prevented had those individuals received the intervention. It was hypothesized that program effects on problematic substance use in young adults would occur indirectly, through the program’s impact on the initiation of substance use. A hierarchical latent growth curve model was used to assess the intervention effects on adolescent substance use initiation, which was then assessed for its effects on young adult substance use outcomes. No subgroup analyses were conducted.