Pre- and post-term children show increased autism risk. Little is known about gestational age (GA) prevalence among autistic children, and their respective autism phenotype. We compared prevalence of pre-, full- and post-term birth between a population-derived sample of N = 606 (137 females, 22.61%) autistic children and adolescents (mean age =…

Using a mixed methods design, this study aimed to examine the impact of the COVID-19 pandemic on autistic and non-autistic adults. We conducted an online survey with 196 autistic and 228 non-autistic adults from Belgium, the Netherlands and the United Kingdom focusing on their experiences during the first period of the pandemic. Our results…

For autism spectrum disorder (ASD) in adults there are several diagnostic instruments available with a need for consideration of the psychometric properties. This study aimed to conduct a first psychometric evaluation of a new diagnostic ASD instrument, the NIDA (Dutch Interview for Diagnostic assessment of ASD in adults) in 90 adult males without…

The actions and feelings questionnaire (AFQ) provides a short, self-report measure of how well someone uses and understands visual communicative signals such as gestures. The objective of this study was to translate and cross-culturally adapt the AFQ into Dutch (AFQ-NL) and validate this new version in neurotypical and autistic populations.…

Autism spectrum disorders are diagnosed globally, but recognition, interpretation and reporting may vary across cultures. To compare autism across cultures it is important to investigate whether the tools used are conceptually equivalent across cultures. This study evaluated the factor structure of the parent-reported Autism Spectrum Quotient…

We investigated the effect of a live online educational program in 93 Dutch Youth and Family Center (YFC) physicians who were screening for Autism Spectrum Disorder (ASD) in the general child population. The educational program raised the physicians' level of specific ASD knowledge and it remained higher at six months follow-up (p < 0.01).…

Autism is associated with a range of costs. This paper reviews the literature on estimating the economic costs of autism spectrum disorder (ASD). More or less 50 papers covering multiple countries (US, UK, Australia, Canada, Sweden, the Netherlands, etc.) were analysed. Six types of costs are discussed in depth: (i) medical and healthcare service…

Since its initial development, the embedded figures test (EFT) has been used extensively to measure local-global perceptual style. However, little is known about the perceptual factors that influence target detection. The current study aimed to investigate "disembedding" in children with and without ASD, aged 8-15 years, using the newly…

In a non-selected sample of children with Neurofibromatosis type 1 (NF1) the prevalence rate of autism spectrum disorder (ASD) and predictive value of an observational (ADOS)--and questionnaire-based screening instrument were assessed. Complete data was available for 128 children. The prevalence rate for clinical ASD was 10.9%, which is clearly…

Children and adolescents with Autism Spectrum Disorder (ASD) often show comorbid emotional and behavior problems. The aim of this longitudinal study is to examine the relation between emotion control (i.e., negative emotionality, emotion awareness, and worry/rumination) and the development of internalizing and externalizing problems. Boys with and…

Studies have shown an increase of symptoms of autism spectrum disorder (ASD) in gender dysphoria (GD). Various hypotheses try to explain this possible co-occurrence (e.g., a role of resistance to change, stereotyped behaviors or prenatal testosterone exposure). This study examined ASD symptoms with the Children's Social Behavior Questionnaire…

Autism spectrum disorder (ASD) characteristics seem to abate over time, but whether this protracts until late adulthood is largely unknown. We cross-sectionally investigated self- and other-reported ASD characteristics of adults with (ASD: N[subscript max-self] = 237, N[subscript max-other] = 130) and without ASD (COM: N[subscript max-self] = 198,…

Primary caregivers experience consequences from being in close contact to a person with autism spectrum disorder (ASD). This study used the Involvement Evaluation Questionnaire to explore the level of consequences of 104 caregivers involved with adults with High Functioning ASD (HF-ASD) and compared these with the consequences reported by…

This RCT investigated whether the effect of a Theory of Mind (ToM) intervention for children with ASD was moderated by parental education level and employment, family structure, and parental ASD. Children with autism aged 8-13 years (n = 136) were randomized over a waitlist control or treatment condition. At posttest, children in the treatment…

Formal thought disorder (FTD) is a disruption in the flow of thought and a common feature in psychotic disorders and autism spectrum disorder (ASD). Executive dysfunction has often been associated with FTD, yet for ASD convincing evidence is lacking. This study investigated FTD and three core executive functions in 50 young children and…