The purpose of this study was to investigate the degree of agreement among parents, teachers and adolescents with respect to the Child Behavior Checklist (CBCL), the Teacher's Report Form (TRF), and the Youth Self Report (YSR). In addition we evaluated the suitability of these three forms (CBCL, TRF and YSR) in terms of their contribution to understanding internalizing and externalizing disorders in youths being referred to a child and adolescent unit of a psychiatric care facility.

A total of 611 patients aged 11–18 years (mean age 13.0, SD 1.6) were assessed using the CBCL, the TRF and the YSR.

Intraclass coefficients (ICC) showed low to moderate agreement among informants. Furthermore, the level of agreement was generally less among patients suffering from internalizing disorders than for young patients who displayed externalizing disorders. Logistic regression revealed that the TRF internalizing syndrome scale, the CBCL internalizing syndrome scale and gender were relevant prognostic factors for the occurrence of internalizing disorders in youth. The YSR internalizing syndrome scale, on the other hand, was not a relevant factor among adolescents of a clinical target population. Likewise, only the TRF externalizing syndrome scale, the CBCL externalizing syndrome scale and gender were relevant prognostic factors for the occurrence of externalizing disorders in youth.

Particularly the CBCL and TRF are useful instruments in assessing internalizing and externalizing disorders in adolescents referred to a mental health setting.