Jakob Øster
Jakob Øster was a paediatrician and school doctor from Randers, Denmark. In 1968, he published a study about the incidence of phimosis, tight prepuce, and smegma in various age-groups. Øster (1968) found that the incidence of fusion of the foreskin with the glans penis steadily declines with increasing age and foreskin retractability increases with age.
Percentage of boys with fused foreskin by age according to Øster