Quebec Child Mental Health Survey: Prevalence of DSM-III-R mental health disorders

The Quebec Child Mental Health Survey (QCMHS) was conducted in 1992 on a re presentative sample of 2400 children and adolescents aged 6 to 14 years fro m throughout Quebec. Prevalences of nine Axis-I DSM-III-R (American Psychia tric Association, 1987) mental health disorders were calculated based on ea ch informant (for 6-11-year-olds: child, parent, and teacher; for 12-14-yea r-olds: child and parent). Informant parallelism allows the classification of results of the demographic variables associated with disorders in the lo gistic regression models. This strategy applies to group variables (correla tes of disorders) whereas informant agreement applies to individual diagnos es. Informant parallelism implies that results for two informants or more a n in the same direction and significant. In the QCMHS, informant parallelis m exists for disruptive disorders, i.e. in two ADHD regression models (chil d and parent) higher rates among boys and young children, and in three oppo sitional/conduct disorders regression models (child, parent, and teacher) h igher rates among boys. No informant parallelism is observed in the logisti c regression models for internalizing disorders, i.e. the patterns of assoc iation of demographic variables with anxiety and depressive disorders vary across informants. Urban-rural residence does not emerge as a significant v ariable in any of the logistic regression models. The overall 6-month preva lences reach 19.9 % according to the parent and 15.8 % according to the chi ld. The implications of the results for policy makers and clinicians are di scussed.