The current study evaluated a brief, informant-based autism interview: the Developmental, Dimensional and Diagnostic Interview -- Adult Version (3Di-Adult). Feasibility, reliability and validity of the Dutch 3Di-Adult was tested amongst autistic participants (n = 62) and a non-autistic comparison group (n = 30) in the Netherlands. The 3Di-Adult…

To examine reliability and validity of the new Social Motor Function Classification System for Children with Autism Spectrum Disorders (SMFCS-ASD). The SMFCS-ASD reliability was examined on 25 children (62.4 months SD 7.8) with ASD among six physical therapists. The validity study involved 1001 children (57.0 months, SD 9.9) with ASD using the…

The Autism Classification System of Functioning: Social Communication (ACSF) describes social communication functioning levels. First developed for preschoolers with ASD, this study tests an expanded age range (2-to-18 years). The ACFS rates the child's typical and best (i.e., capacity) performance. Qualitative methods tested parent and clinician…

This study examined the validity of the Greek version of the Societal Attitudes Towards Autism (SATA) scale in a Greek community sample (n = 633) and explored how the demographic variables of the sample modulate knowledge and attitudes regarding people with Autism Spectrum Disorder (ASD). The principal component analysis confirmed the…

Quality of life (QOL) and life satisfaction are important research priorities for autistic adults. As such, we saw a need to evaluate individual items of commonly used subjective QOL scales to understand how they are interpreted and perceived by autistic adults. This study used cognitive interviews and repeated sampling to evaluate the…

Use of telehealth assessments for toddlers at increased likelihood of autism spectrum disorder (ASD) began prior to the global COVID-19 pandemic; however, the value of telehealth assessments as an alternative to in-person assessment (IPA) became clearer during the pandemic. The Naturalistic Observation Diagnosis Assessment (NODA™), previously…

CDKL5 deficiency disorder (CDD) results in early-onset epilepsy and lifelong cognitive and motor impairments. With no validated measure for communication in CDD, this study evaluated the psychometric properties of the Communication and Symbolic Behavior Scales-Developmental Profile Infant Toddler Checklist (CSBS-DP ITC). Caregivers (n = 150;…

Reliably diagnosing autism spectrum disorders (ASD) in adulthood poses a challenge to clinicians due to the absence of specific diagnostic markers. This study investigated the potential of interpersonal synchrony (IPS), which has been found to be reduced in ASD, to augment the diagnostic process. IPS was objectively assessed in videos…

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.…

Previous research shows inconsistency in clinician-assigned diagnoses of Autism Spectrum Disorder (ASD). We conducted an exploratory study that examined the concordance of diagnoses between a multidisciplinary assessment team and a range of independent clinicians throughout Australia. Nine video-taped Autism Diagnostic Observation Schedule (ADOS)…

Little is known about the across time stability of autistic traits during the transition period from preschool to school age in the general population. The current study compared autistic traits assessed by a mother-reported quantitative measure, the Social Responsiveness Scale, at age 5 and 8 years and examined the intraclass correlation…

Our purpose in this study was to further examine the psychometric properties of the Quality of Life for Children with Autism Spectrum Disorder (QOLASD-C) scale. We first investigated the factor structure and the internal consistency of the scale. The bifactor model showed good fit and strong reliability. Second, we used multiple-indicators…

This study proposes a multi-informant (youth, teachers, and parents) measure of relationship quality with adults for youth with intellectual disabilities (ID). A sample of 395 youth with mild (49.15%) and moderate (50.85%) ID, aged 11-22 (M = 15.82) was recruited in Canada (French-speaking, N = 142), and Australia (English-speaking, N = 253).…

The Participation and Sensory Environment Questionnaire-Teacher Version (PSEQ-TV) is a teacher-report questionnaire to assess the impact of the sensory environment on participation of preschool children with autism spectrum disorder (ASD). Many children with ASD have sensory processing differences, although these differences are frequently…

Deficits in perceptual constancies from early infancy have been proposed to contribute to autism and exacerbate its symptoms (Hellendoorn et al., "Frontiers in Psychology" 6:1-16, 2015). Here, we examined size constancy in adults from the general population (N = 106) with different levels of self-reported autistic traits using an…