Page 22 - Age of onset of disruptive behavior of residentially treated adolescents -Sjoukje de Boer

Outline of the thesis
As described before, the present thesis aimed at identifying subgroups based on the age of onset of disruptive behavior in a heterogeneous group of youths with a combination of psychiatric disorders and severe disruptive behavior. Subsequently, these subgroups were related to proximal and distal outcomes. The starting point was the distinction between LCP and AL antisocial behavior as described by Moffitt and colleagues (1993) based on a general population sample followed from birth until adulthood. Contrary to this prospective study, the sample in the present thesis was first assessed by us at adolescent age. All participants displayed severe disruptive behavior at the time of their admission (mean age 17). Based on that behavior, it was not possible to distinguish individuals with potential LCP or AL disruptive behavior. Thus, one of the first challenges of the present thesis was to find out whether it was possible make a distinction in onset of disruptive behavior in retrospect. In Chapter 2, we examined youth health care files of a subsample (n=24) of the 294 participants. In these files, that had been kept up from early infancy, we focused on written comments made by health professionals or teachers at the time that the respondents were five years of age. In these files, professionals were not specifically questioned about disruptive behavior, they just had the opportunity to indicate any striking features of the child. We compared the files of the subsample with those of a control group, who later on, in adolescence had no reported history of behavioral or psychiatric problems. The aim was to examine whether early in their lives both groups differed on reported signs of disruptive behavior.
The aim of Chapter 3 was to examine whether individuals with EO disruptive behavior differed from individuals with AO disruptive behavior on childhood characteristics. Childhood characteristics were considered that were associated with LCP antisocial behavior and we examined whether they were also present in youths classified as EO.
It was suggested that individuals with LCP antisocial behavior would be less susceptible to treatment compared to individuals with AL antisocial behavior (Moffitt et al., 2008; Moffitt et al., 1996), however, this had never been examined. Therefore, the aim of Chapter 4 was to compare the outcome (i.e., reduction of symptoms
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