The MacArthur Competence Assessment Tool-Criminal Adjudication: Factor structure, interrater reliability, and association with clinician opinion of competence in a forensic inpatient sample.

Abstract

Adjudicative competence is the most frequently referred evaluation in the forensic context, and it is because of this that periodic evaluation of competence assessment instruments is imperative. Among those instruments, the MacArthur Competence Assessment Tool-Criminal Adjudication (MacCAT-CA) has demonstrated adequate psychometric properties suggesting its utility in informing the forensic inquiry. The purpose of the current study was to further investigate the psychometric properties and ultimate utility of subscale scores using archival data from a sample of 103 male and female forensic patients who were hospitalized for competence restoration treatment. Results of the present study suggested adequate internal consistency and good model fit for the factor structure. Interrater reliability was evaluated by comparing the absolute agreement of scores derived from 2 independent research assistants for each of the subscales; 2 of the 3 subscales fell within the acceptable range given established interpretative benchmarks for forensic assessment. Of particular interest was that the Appreciation subscale, while heralding the lowest intraclass correlation coefficient, explained the largest proportion of variance in clinician opinion relative to the other 2 subscales. In other words, the most subjective subscale (as evidenced by the lowest intraclass correlation), explained the largest proportion of variance in ultimate opinion. The authors argue that, although these results are an important consideration in these assessments, they are neither surprising nor entirely problematic when considering the case-specific nature of the inquiries on the subscale, as well as the subjectivity of scoring criteria for each of the Appreciation items. (PsycINFO Database Record