Clinical correlates of diagnostic certainty in children and youths with Autistic Disorder.

Background: Clinicians diagnosing autism rely on diagnostic criteria and instruments in combination with an implicit knowledge based on clinical expertise of the specific signs and presentations associated with the condition. This implicit knowledge influences how diagnostic criteria are interpreted, but it cannot be directly observed. Instead, insight into clinicians' understanding of autism can be gained by investigating their diagnostic certainty.

Examining the validity of the use of ratio IQs in psychological assessments.

Intelligence tests are amongst the most used psychological assessments, both in research and clinical settings. To avoid missing data points, for participants who cannot complete Intelligence tests normed for their age, ratio IQ scores (RIQ) are routinely computed and used as a proxy of IQ. Here, we use the case of autism to examine the validity of this widely used, yet never scientifically validated, practice.

A longitudinal study on language acquisition in monozygotic twins concordant for autism and hyperlexia.

Background: Hyperlexia, a strong orientation towards written materials, along with a discrepancy between the precocious acquisition of decoding skills and weaker comprehension abilities, characterizes up to 20% of autistic children. Sometimes perceived as an obstacle to oral language acquisition, hyperlexia may alternatively be the first step in a non-social pathway of language acquisition in autism.

Method: We describe two monozygotic twin brothers, both autistic and hyperlexic, from the ages of 4 to 8 years old.

A longitudinal comparison of emotional, behavioral and attention problems in autistic and typically developing children.

Background: Mental health problems are elevated in autistic individuals but there is limited evidence on the developmental course of problems across childhood. We compare the level and growth of anxious-depressed, behavioral and attention problems in an autistic and typically developing (TD) cohort.

Methods: Latent growth curve models were applied to repeated parent-report Child Behavior Checklist data from age 2-10 years in an inception cohort of autistic children (Pathways, = 397; 84% boys) and a general population TD cohort (Wirral Child Health and Development Study; WCHADS; = 884, 49% boys).