To evaluate the epidemiological findings of idiopathic scoliosis in eleven years olds.

A total of 18,521 adolescents who were eleven years old were screened for scoliosis. There were 10,204 boys and 8,317 girls. The adolescents who had an abnormal moire topography were assessed subsequently using standardized clinical and radiological examinations. The scoliotic curve was defined as a curve of 10 or more.

The prevalence of scoliosis was 0.31 per cent (57 of 18,521 adolescents), and most of the curves (42; prevalence, 0.23 per cent) were small (10 to 19 °). The ratio of boys to girls was 1:4.7 overall. Thoracolumbar curves were the most common type of curve identified, followed by thoracic and lumbar curves.

The prevalence of idiopathic scoliosis in eleven year olds was 0.31 per cent. The size and pattern of idiopathic scoliosis were similar with those in the adolescents twelve years and older reported in the literature.