The ADD is a 79-item psychopathology screening instrument representing 13 diagnostic categories. They include: Mania, Depression, Anxiety, PTSD, Substance abuse, Somatoform disorders, Dementia, Conduct disorder, Pervasive developmental disorder, Schizophrenia, Personality disorders, Eating disorders, and Sexual disorders. Parents/caretakers familiar with the individual rates each item. Sample items include, 'Has difficulty controlling worries'; 'Feels decreased need for sleep'; 'Has bizarre delusions'; 'Hears voices'; and 'Frequently lies.'

References:

Matson, J.L. (1997). The Assessment for Dual Diagnosis (ADD). Baton Rouge, LA: Disability Consultants, LLC.

Matson, J. L., & Bamburg, J. W. (1998). Reliability of the Assessment of Dual Diagnosis (ADD). Research in Developmental Disabilities, 19(1), 89-95.

McDaniel, W. F., Passmore, C. E., & Sewell, H. M. (2003). The MMPI-168(L) and ADD in assessing psychopathology in individuals with mental retardation: Between and within instrument associations. Research in Developmental Disabilities, 24(1), 19-32.