Subtypes of learning disabilities : Neuropsychological and behavioural functioning of 495 children referred for multidisciplinary assessment

Aim of the present study was two fold: (1) to evaluate the course of referring and diagnosing Learning Disabilities (LD) and the contribution of multidisciplinary assessment and (2) to describe characteristics of three LD subtypes: Attention with or without Motor function Disabilities (AMD), Verbal Learning Disabilities (VLD) and Non-Verbal Learning Disabilities (NVLD). Diagnostics, behavioural and neuropsychological data from 495 children aged 6-17 years were described. First, AMD and VLD was the most frequent LD. Multidisciplinary assessment could contribute to the diagnostic process of LD, especially in diagnosing uncommon LD and comorbidities. Secondly, behavioural ratings, information processing, attention regularity and visual-motor integration proved to be most sensitive in discriminating between the three LD subtypes. However, diagnosing NVLD requires additional developmental information. Multiple discriminant function analysis correctly classified 61.7% of a selection of the present sample into LD subtypes as diagnosed by the multidisciplinary team. It is believed that the three subtypes are clinically relevant and suggestions are made to test the present classification functions in an independent sample, preferably diagnosed using a structured diagnostic interview.