One in 10 high school students in the U.S. reports having been hit or physically hurt by a dating partner in the past year, according to a new study by Boston University School of Public Health researchers. In a study published in the Journal of School Violence, Dr. Emily Rothman and Dr. Ziming Xuan of Boston University School of Public Health analyzed data from 100,901 students who participated in the national Youth Risk Behavior Surveillance System survey for the years 1999-2011. They found that 9.3 percent of U.S. high school students have been “hit, slapped, or physically hurt on purpose” by a boyfriend or girlfriend in the past year – an annual prevalence rate that has not changed significantly in the past 12 years.