A sequence variant associating with educational attainment also affects childhood cognition.

Only a few common variants in the sequence of the genome have been shown to impact cognitive traits. Here we demonstrate that polygenic scores of educational attainment predict specific aspects of childhood cognition, as measured with IQ. Recently, three sequence variants were shown to associate with educational attainment, a confluence phenotype of genetic and environmental factors contributing to academic success.

CNVs conferring risk of autism or schizophrenia affect cognition in controls.

In a small fraction of patients with schizophrenia or autism, alleles of copy-number variants (CNVs) in their genomes are probably the strongest factors contributing to the pathogenesis of the disease. These CNVs may provide an entry point for investigations into the mechanisms of brain function and dysfunction alike. They are not fully penetrant and offer an opportunity to study their effects separate from that of manifest disease.

Long-term outcome of medically confirmed and self-reported early traumatic brain injury in two nationwide samples.

Primary Objectives: To assess long-term effects of early traumatic brain injury (TBI) on mental health, cognition, behaviour and adjustment and to identify prognostic factors.

Methods And Procedures: A 1-year nationwide cohort of all 0-19 year old Icelandic children and adolescents diagnosed with TBI in 1992-1993 (n = 550) received a questionnaire with clinical outcome scales and questions on TBI and socio-economic status (SES) by mail ∼16 years post-injury. A control group (n = 1232), newly selected from the National Registry, received the same questionnaire.

The Adult Reading History Questionnaire (ARHQ) in Icelandic: Psychometric Properties and Factor Structure.

This article describes psychometric testing of an Icelandic adaptation of the Adult Reading History Questionnaire (ARHQ), designed to detect a history of reading difficulties indicative of dyslexia. Tested in a large and diverse sample of 2,187 adults, the Icelandic adaptation demonstrated internal consistency reliability (Cronbach's alpha = .92) and test-retest reliability (r = .

The scope of early traumatic brain injury as a long-term health concern in two nationwide samples: prevalence and prognostic factors.

Primary Objectives: To examine the scope of paediatric traumatic brain injury (TBI) as a health concern and to identify prognostic factors for TBI-related sequelae.

Methods And Procedures: The study was prospective and nationwide. A questionnaire was sent to a study group (SG) of all 0-19 years old in Iceland, diagnosed ∼16 years earlier with TBI during a 1-year period, 1992-1993 (n = 550) and to a control group (CG) (n = 1232), selected from the National Register.

The prognostic value of injury severity, location of event, and age at injury in pediatric traumatic head injuries.

Aims: To estimate the prognostic value of injury severity, location of event, and demographic parameters, for symptoms of pediatric traumatic head injury (THI) 4 years later.

Methods: Data were collected prospectively from Reykjavik City Hospital on all patients age 0-19 years, diagnosed with THI (n = 408) during one year. Information was collected on patient demographics, location of traumatic event, cause of injury, injury severity, and ICD-9 diagnosis.

Urban-rural differences in pediatric traumatic head injuries: A prospective nationwide study.

Aims: To estimate differences in the incidence of recorded traumatic head injuries by gender, age, severity, and geographical area.

Methods: The study was prospective and nationwide. Data were collected from all hospitals, emergency units and healthcare centers in Iceland regarding all Icelandic children and adolescents 0-19 years old consecutively diagnosed with traumatic head injuries (N = 550) during a one-year period.