Inter-rater and test-retest reliability, as well as internal validity, have been demonstrated for the ADI-R.
Test-retest reliability and interrater reliability were assessed in unselected clinical (n = 50) and nonclinical (n = 30) populations. Concurrent validity (n = 120), discriminant validity (n = 120), and criterion validity (n = 29) were evaluated in Autistic Spectrum and non-Autistic patients. Results: Test-retest and interrater reliabilities were excellent (most intraclass correlation coefficients > 0.9).
The factor structure, internal consistency, and convergent validity of the Autism ADI-R algorithm items were examined in a sample of 226 children with Pervasive Developmental Disorders. Exploratory factor analyses indicated a three-factor solution closely resembling the original algorithm and explaining 38% of the variance, with one significant discrepancy. Unlike the algorithm, all nonverbal communication items were associated with the Social factor. Internal consistencies of domain scores ranged from .54 to .84. Correlations between ADI-R domain and total scores and instruments assessing adaptive behavior, psychopathology, and Autism were examined. They indicated some similarities between constructs, but also that the ADI-R measures Autism in a unique fashion.
Concurrent validity (agreement with independent clinician formulation) was very good (mean [kappa] = 0.74). Criterion validity, a comparison with the Autism Diagnostic Interview, was excellent. Discrimination between Autistic Spectrum versus non-Autistic subjects was almost perfect (sensitivity 1.0; specificity > 0.97). Back to the top
- Summary of Response Reports paraphrase each question and response, including information typed by the respondent for those categories that request descriptive information.
- Concise Reports of Possible Diagnoses list whether or not criteria have been met for a possible diagnosis.
- Possible Diagnoses and Criteria Reports include additional information based on the DSM-IV™, such as the specific criteria met and the responses as they relate to each diagnosis. Back to the top
Ann Le Couteur, M.B.B.S.
Ann Le Couteur, M.B.B.S. works within a multidisciplinary clinical academic team that provides specialist clinical services for children and young people with complex neurodevelopmental disorders including Autism Spectrum Disorders (ASDs). Current research interests include the etiology of ASD; evaluation of interventions for children and families; and the promotion of models of assessments and treatment. She chaired the work of a national working party that led to the publication of The National Autism Plan for Children (2003) and is involved with a number of UK charities for children and young people with complex needs. Back to the topCatherine Lord, Ph.D.
Catherine Lord, Ph.D. is a clinical psychologist whose research focuses on the development of children and adults with Autistic Spectrum Disorders; including longitudinal studies of children referred for possible Autism as toddlers, and in collaboration with many colleagues the development of instruments for the diagnosis of Autistic Spectrum Disorders and the quantification of social, communication and behavioral features associated with autism and related developmental disabilities. These instruments have been important in providing standardized methods for research on the genetics and neurobiology of Autism because they provide psychometrically valid and reliable tools for identification and specification of the behaviors that define autism. In addition, study of the process of diagnosis and of longitudinal change has provided intriguing insights into the nature of the social and behavioral deficits of these children.
Catherine is Chair of the Early Intervention in Autism Committee, National Academy of Science. She received the Irving B. Harris Early Childhood Lecture Award in 2004 and was a Finalist for the New York University Child Study Center Scientific Achievement Award in 2005. Back to the top