Factor structure of the Comprehensive Adolescent Severity Inventory (CASI): results of reliability, validity, and generalizability analyses.

This article describes the results of psychometric work conducted on the Comprehensive Adolescent Severity Inventory (CASI) among 205 in-treatment substance-abusing adolescents. Four dimensions, each composed of component subscales, resulted from standard psychometric analyses: Chemical Dependency, Psychosocial Functioning, Delinquency, and Risk Behavior. Each dimension had high internal consistency (alpha coefficients for the component subscales comprising each clinical dimension range from .78 to .96) and test-retest reliability (intraclass correlation coefficients range from .88 to .96 and all are significant at p < .0001.). Concurrent validity and specificity of the CASI dimensions also were found: significant and substantial variance in NIMH Diagnostic Interview Schedule for Children-Revised (DISC-IV) and Brief Symptom Inventory (BSI) scores was associated with relevant CASI dimensions; CASI dimensions that theoretically should show no significant relationship with divergent pathology were not associated. The dimensions forecasted substantial variance in adolescent functioning posttreatment discharge, supporting predictive validity. Finally, the dimensional clinical structure was found to be generalizable over male and female adolescents, younger and older adolescents, and adolescents from different ethnic groups. These results provide further evidence for the CASI's promise in research and practice as an adolescent-specific assessment instrument that comprehensively assesses multidimensional areas of functioning within a developmental context of measurement. Limitations of the study along with future work currently being conducted on the CASI are discussed.