BackgroundThe aim of this study was to assess the association between the clinical and neurobiological markers of neurodevelopmental impairments and early-onset schizophrenia spectrum psychosis.MethodsA sample of 36 patients with early-onset schizophrenia spectrum psychosis was compared to a control sample of 36 patients with migraine. We assessed early childhood neurodevelopmental milestones using a modified version of the General Developmental Scale, general intellectual ability using the Wechsler Intelligence Scale for Children–Revised or Leiter International Performance Scale–Revised for patients with speech and language abnormalities, and neurological soft signs with specific regard to subtle motor impairment.ResultsSubjects with early-onset psychosis had a higher rate of impaired social development (P=0.001), learning difficulties (P=0.04), enuresis (P=0.0008), a lower intelligence quotient (P<0.001), and subtle motor impairments (P=0.005) than control subjects.ConclusionWe suggest that neurodevelopment in early-onset psychosis is characterized by a global impairment of functional and adaptive skills that manifests from early childhood, rather than a delay or limitation in language and motor development. The current evidence is based on a small sample and should be investigated in larger samples in future research.