A review of methodological issues in the differential diagnosis of autism spectrum disorders in children

The development of standardized tests to assess autism, particularly in young children, is a topic of considerable interest in the research Community. Recent years have seen an exponential growth in scales for differential diagnosis. Particular emphasis has been placed on defining and better delineating the symptoms of the disorder relative to other forms of autism spectrum disorder (ASD) and intellectual disability (ID), and identifying the condition at the earliest possible age. The general consensus is that scaling methods are the core means of establishing a diagnosis. Thus, analyzing the research activity in the area for strengths and weaknesses in methodology would appear to be in order. A critical overview of existing psychometric properties of these tests is presented with suggestions for future research on the topic. (C) 2006 Elsevier Ltd. All rights reserved.