EMPIRICALLY DEFINED SYMPTOM SCALES USING THE DISC-2.3

Empirically defined scales of depressive, attention deficit hyperactiv ity disorder, oppositional-defiant disorder, and conduct symptoms from the lay-administered National Institute of Mental Health (NIMH) Diagn ostic Interview Schedule for Children (DISC), version 2.3, and evidenc e of their reliability and validity are presented. The scales were dev eloped using factor analyses of data obtained from an epidemiologic su rvey of over 1,200 children drawn from four sites across the U.S. and Puerto Rico (the NIMH Methods for the Epidemiology of Child and Adoles cent Mental Disorders, or MECA Study). Their psychometric properties w ere rested in a subsample of children reinterviewed by clinicians. The findings support the use of these continuous measures. The scales are strongly related to the diagnostic categories and show good test-rete st reliability. The scales can be used to characterize severity in chi ldren with diagnoses and to describe problems and symptoms in children without diagnoses. Because these scales can measure gradations in sym ptomatology, they may be more useful than categorical measures. Like c ategorical measures the scales based on the DISC are greatly influence d by the informant, whether child or parent.