Around a quarter of adolescent girls who have been in relationships have endured physical or sexual violence, a World Health Organization study said on Tuesday, calling for more prevention actions. The WHO analysis published in the Lancet medical journal was based on surveys from thousands of adolescent girls aged between 15 and 19 from 154 countries and areas. It showed that 24% of them had been subjected to intimate partner violence at least once, with 16% reporting it in the past year.