an examination of the factor structure of the psychopathy checklist

Further, based on the relatively low prevalence of alcohol and/or drug use prior to or
during the offence, these substances were not a major factor in many of the violent
offences that were considered in the current study, making it difficult to determine their
relationship to offence motivation.
Given the relative recency of the application of the continuous instrumental
aggression measure, the ARF, the construct validity of this measure was assessed. As
previously noted, the construct validity of this measure was initially evaluated among an
exclusively male adolescent sample (see Vitacco et al., 2006). This study was the first
to assess the validity of this new measure among a female sample. Results
demonstrated that the ARF’s single factor model was not a good fit among this sample
of violent female youth, however, fit indices did approach the standards set out by Hu
and Bentler (1999) for an adequate fitting model. Interestingly, the presence of two
features (i.e., goal directed and planning or preparation) best represented the construct
of instrumental aggression which suggests that these two characteristics of aggression
are principal components of instrumental aggression among female youth. Vitacco and
colleagues, among their exclusively male sample, found that three features best
represented the construct of instrumental aggression: goal directed, unprovoked, and a
lack of anger during the aggression; however, among the current sample, the latter two
characteristics were identified as weak and moderate features, respectively, of the
construct of instrumental aggression. Based on the findings from current female sample,
as well as Vitacco et al.’s (2006) exclusively male sample, it is evident that goal-
directedness is a fundamental feature of instrumentality since it is a shared feature in
the aggressive acts of both male and female youth. Alternately, the findings from this
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