The Modified Checklist for Autism in Toddlers, Revised with Follow-up was validated on a population sample in Reykjavik, Iceland. The participants (N = 1585) were screened in well-child care at age 30 months and followed up for at least 2 years to identify autism cases. The sensitivity, specificity, positive and negative predictive values were…

We estimated autism spectrum disorder (ASD) prevalence in 7-9 year-old children in 2015 using data from three nationwide health registry systems (Denmark, Finland, Iceland) and two French population-based regional registries. Prevalence ranged from 0.48% in South-East France to 3.13% in Iceland (South-West France: 0.73%, Finland: 0.77%, Denmark:…

The prevalence of autism/autism spectrum disorder (ASD) has been increasing across the world. Previous studies in Norway reported, that the prevalence rate for 0-10-year-old children is 1 in 166, and in the case of 11-year-old children it is 1 in 125. Moreover, another nationwide study discovered that 1 in 192 males and 1 in 695 females between…

This study compared children with early and late diagnosis of autism spectrum disorder (ASD). All children in four consecutive birth cohorts in Iceland diagnosed with ASD were divided into two groups based on their age at initial ASD diagnosis: 58 children were diagnosed before age 6 (group 1) and 41 children after age 6 (group 2). Children in…