The purpose of this study was to evaluate the long-term adjustment of adolescents whose early-onset conduct problems were treated with the IY Parenting Program utilising standardised measures and comparison to national, normative US samples. Overall, findings indicated that the treated children showed less severe indications of conduct problems at adolescence than might have been expected (e.g. limited criminal justice system involvement) given their early onset clinical levels. Findings also indicated that high post-treatment levels of parent-child coercion and child externalising problems were associated with the adolescent problem outcomes. Parental stress at post treatment was not associated with long-term problems.
At long-term follow-up, 16% and 12% of the teens were in the clinical range according to mother and father reports respectively on the CBCL externalising scale, compared to 25% and 10%, immediately post-treatment. Thus, parent reports of externalising problems were stable or slightly improved over the follow-up period.
In terms of adolescent antisocial behaviours that we hoped to prevent, approximately half of the teens (46%) reported some lifetime use of drugs or alcohol. This is somewhat consistent with national norms of lifetime drug use (34%) and alcohol use (58%). Our sample reported less sexual activity than normal: 21% had engaged in sexual intercourse compared to 47.8% in a US national sample. In terms of delinquency and criminal justice system involvement, our sample showed a majority of teens (78%) who engaged in one or more minor delinquent acts, but only a few (23%) who exhibited major delinquent acts. There were 12 (18%) who were involved in the criminal justice system. These numbers are somewhat consistent with national norms. Numbers of students in our sample who had been expelled from school were high (12.7%) compared to national norms; but it is important to highlight that only one of the teenagers in this sample of 66 had dropped out of school and this was the teenager who had become pregnant. None of the teenagers from our study had served any time in juvenile detention or jail. In addition to the normative samples presented above, we compared our teenagers (grades 7–12) to a similar age group of boys assessed in 8th
grade and again in 10th
grade who had participated in a longitudinal study (OYS; Wiesner et al., 2005
). These comparison boys had not been identified as having had early behaviour problems like the children in our sample. Data indicated that our treated teenagers engaged in about the same or fewer delinquent acts as this comparison group and had similar sexual activity. Our group reported greater abstinence from substance abuse (56.9%) than the comparison group (32% in grade 8 and 29.5% in 10th
grade) and less involvement with the criminal justice system (18% our sample, 54% OYS sample) suggesting the success of the program in preventing and reducing these behaviours.
Our sample exhibited very low levels of internalising problems. According to mother and father reports on the CBCL, respectively 12% and 8% of teens exhibited a clinically significant number of internalising symptoms. A few (10%) of the adolescents self-reported elevated symptoms of depression, anxiety, or low self-worth. Since early externalising problems have been shown to predict long-term internalising problems (Fischer et al., 1984
), it is encouraging to find so few teens with internalising problems.
A second aim of the study was to determine whether family demographic factors or post-treatment parenting or child behaviour factors were associated with poor long-term outcomes. Results indicated that SES did not significantly predict long-term outcomes. However, immediate post treatment mother reports of conduct problems and low rates of mother praise did significantly predict teenager reports of delinquent acts. Post-treatment mother reports of conduct problems and coercive behaviour predicted teenager involvement in the criminal justice system.
When the clinical or nonclinical levels of post-treatment outcomes were used as the predictor of long-term outcomes, a similar result was found. Children with clinical post-treatment scores on the ECBI were more likely to engage in adolescent delinquent-acts (44%) than those whose post-treatment reports were in the normal range (12%). Children who were observed to have high post-treatment rates of deviant behaviour showed higher rates (28.6%) of criminal justice system involvement than those with lower rates of deviant behaviour (8.1%). Mothers who were observed to have high post-treatment rates of critical behaviour had adolescents with significantly higher rates (31.8%) of criminal justice system involvement than those with lower rates of critical behaviour (9.3%).
Our prior research has suggested that more than 10 critical parent statements or 10 child deviant and noncompliant behaviours during the 30-minute observation is in the clinical range (Webster-Stratton & Hammond, 1998
). In the current study, when this level of improvement in coercion was not achieved post treatment, there was a higher likelihood of poor outcomes. Perhaps these mother-child interactions were more difficult to change, possibly because their children were more negative to begin with, or had more biological and developmental factors, or because there were other family risk factors such as substance abuse, spousal conflict or depression that disrupted parenting interactions. To make lasting improvements, these families would seem to need continued intervention to focus on these special parent or child needs in order to further reduce their coercion levels to below the threshold and promote more sustained positive parenting.
A few limitations of this study deserve comment. First, the follow-up sample does not include an untreated control group; thus there is no direct comparison of comparable children who did not receive the IY intervention. However, it is noteworthy that the rates of adolescent behaviours in our study are somewhat consistent with US-based, national published, age-related norms for children ages 12 to 19 on delinquent acts (Elliott et al., 1983
), substance use (National Institute on Drug Abuse, 2009
), school expulsion rates (National Center for Education Statistics, 2006
), and involvement with the criminal justice system (Elliott et al., 1983
), as well as with a longitudinal study of boys from the Oregon Youth Study (OYS; Wiesner et al., 2005
). Nonetheless, future research designs addressing long-term effectiveness need a randomised control group trial since the normative data provided here are based on a variety of different samples, and can only provide loose guidelines for comparison to our sample. A second limitation is that the sample includes a wide age range from a few young adolescents who might not yet be showing severe conduct problems to the later adolescent years, which represent the time in the developmental life span where youth typically exhibit the highest rates of antisocial activities. A later follow-up assessment when all of the children in this study have reached young adulthood would allow us to see whether these youth moved through this adolescent risk behaviour into typically functioning young adults or whether they continued on a trajectory of delinquency and antisocial behaviour. Lastly, almost no data were collected on intervention received by youth or their families during the follow-up period. A brief assessment collected 2 years after the original intervention indicated that, at that time, 17% of the sample was taking medication for ADHD, 19% was receiving special education programs at school, and 26% had received further therapy. However, information on the duration and intensity of these services was not collected. It would be valuable to know what role on-going intervention played in the long-term outcomes for these children.
The results from this study are encouraging in that the majority of the teenagers who received treatment for early-onset conduct problems were well adjusted and rates of risky behaviours seemed within the normal limits for typical adolescents according to national normative data. For those teenagers who were exhibiting delinquent behaviours and criminal justice system involvement, this study was useful in identifying post-treatment risk indices in early childhood, which predict long-term poor outcome. Most importantly, mothers who still reported clinical levels of aggressive behaviour in their young children post treatment or are observed with high levels of coercive interactions post treatment should be taken seriously, as their children are at higher risk of continued antisocial problems in adolescence. This supports the notion that it is necessary to continue treatment until coercion is reduced to a clinically significant threshold level in order to maintain improvements and prevent adolescent delinquency and criminal involvement.
Key Practitioner Message
- Positive outcomes from early intervention for children with conduct problems were mostly maintained 8–10 years later
- Level of post-treatment parent-child coercion predicted adolescent outcomes
- It may be important to reduce parent-child coercion below a clinically significant threshold
- In families where levels of parent-child coercion are still high post-treatment, further intervention may be warranted to prevent future problems