ASD is one of the most heritable neuropsychiatric disorders, though comprehensive genetic liability remains elusive. To facilitate genetic research, researchers employ the concept of the broad autism phenotype (BAP), a milder presentation of traits in undiagnosed relatives. Research suggests that the BAP Questionnaire (BAPQ) demonstrates…

The World Health Organization's Quality of Life Questionnaire-BREF (WHOQOL-BREF) has been used in many studies that target parents of children with Autistic Disorder. However, the measure has yet to be validated and adapted to this sample group whose daily experiences are considered substantially different from those of parents of children…

With the publication of the "Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition", autism spectrum disorders are defined by two symptom clusters (social communication and restricted/repetitive behaviors) instead of the current three clusters. The current study examined the structure of the Baby and Infant Screen for…

The current study was motivated by a need for a self-report questionnaire that assesses a broad range of subthreshold autism traits, is brief and easily administered, and is relevant to the general population. An initial item pool was administered to 1,709 students. Structural validity analysis resulted in a 24-item questionnaire termed the…

The current study tested several competing models of the autism phenotype using data from modules 1 and 3 of the ADOS. Participants included individuals with ASDs aged 3-18 years (N = 1,409) from the AGRE database. Confirmatory factor analyses were performed on total samples and subsamples based on age and level of functioning. Three primary…

Background: Multivariate statistics can assist in refining the nosology and diagnosis of pervasive developmental disorders (PDD) and also contribute important information for genetic studies. The Autism Diagnostic Interview-Revised (ADI-R) is one of the most widely used assessment instruments in the field of PDD. The current study investigated its…

The factor structure of the Dutch translation of the Autism-Spectrum Quotient (AQ; a continuous, quantitative measure of autistic traits) was evaluated with confirmatory factor analyses in a large general population and student sample. The criterion validity of the AQ was examined in three matched patient groups (autism spectrum conditions (ASC),…

Background: A number of disorders are associated with pragmatic difficulties. Instruments that can make subdivisions within the larger construct of pragmatics could be important tools for disentangling profiles of pragmatic difficulty in different disorders. The deficits underlying the observed pragmatic difficulties may be different for different…