Pieter F. A. de Nijs

Learn More
Rates of co-morbid psychiatric conditions in children with Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS) are hardly available, although these conditions are often considered as more responsive to treatment than the core symptoms of PDD-NOS. Ninety-four children with PDD-NOS, aged 6-12 years were included. The DISC-IV-P was administered.(More)
BACKGROUND Comorbidity between anxiety disorders and depressive disorders in adolescents occurs very frequently. The aim of this study was to investigate if anxiety and depression represent distinct disease entities. METHODS Two thousand thirty two 11- to 18-year-olds, referred to mental health services, were investigated. Self-reported symptoms of(More)
This study aimed to contribute to the Diagnostic and Statistical Manual (DSM) debates on the conceptualization of autism by investigating (1) whether empirically based distinct phenotypic profiles could be distinguished within a sample of mainly cognitively able children with pervasive developmental disorder (PDD), and (2) how profiles related to diagnoses(More)
Autistic features such as deficits in social interactions and communication have been associated with a low 2D:4D ratio in normal children.This study assessed this association in a large sample of children with a variety of psychiatric disorders (n = 35 girls and n = 147 boys). Autistic features were assessed with a highly valid and reliable measure (Autism(More)
The objective of this study was to identify behavioral differences between children with multiple complex developmental disorder (MCDD) and those with pervasive developmental disorder-not otherwise specified (PDD-NOS). Twenty-five children (6-12 years) with MCDD and 86 children with PDD-NOS were compared with respect to psychiatric co-morbidity, psychotic(More)
The current 7-year follow-up study investigated: (1) the stability of ASD severity, and (2) associations of ASD severity in adolescence with (a) childhood and concurrent psychiatric comorbidity, and (b) concurrent societal functioning. The Autism Diagnostic Observation Schedule (ADOS) and the Diagnostic Interview Schedule for Children were administered in(More)
This study evaluated the ability of the Child Behavior Checklist and the Teacher's Report Form to identify children with autism spectrum disorders (ASD), using a sample of children with ASD (n = 458), referred children without ASD (n = 1109) and children from the general population (n = 999). A ten items ASD scale was constructed using half of the sample(More)
BACKGROUND Previous studies have found considerable overlap between attention/hyperactivity problems, aggressive/oppositional problems and delinquent/conduct problems in adolescents. SAMPLING AND METHODS Mothers of 1,965 11- to 18-year-olds (1,116 boys, 849 girls), referred to mental health agencies, completed the Child Behavior Checklist (CBCL). Latent(More)
BACKGROUND There is growing interest in autism spectrum disorders (asd) in adulthood. Someone can be diagnosed with ASD, but the diagnosis tells us very little about the patient’s temperament, character and personality. Comparatively little is known about the personality traits of persons with ASD. AIM To map personality traits of persons with asd.(More)
This retrospective longitudinal study in young children with neurofibromatosis type 1 (NF1) aimed to identify if, and how early problems in behavior, intelligence, and language development are associated with later behavioral problems. At the first assessment at preschool age, we evaluated language skills, intelligence, and emotional and behavioral problems(More)