The frequency of school violence is higher in upper grades than lower grades, a survey has found, with 1 in 3 high school victims experiencing peer-to-peer violence almost every day, data showed Monday.

According to an in-depth analysis of school violence conducted by the Korea Educational Development Institute, 0.3 percent of high schoolers reported being victims of school violence in the past year, while the rates for elementary and middle school students were 2.9 percent and 1 percent, respectively.

Among the victims, 32 percent of high schoolers said they experienced abuse almost every day. The rate was 23.6 percent for middle school students and 20 percent for elementary students, showing that bullying gets worse in upper grades.

The report also found that lower graders were more prone to school violence, but the frequency of school violence was highest in older age groups. Also, 68.3 percent of school violence incidents happened between students in the same grade.

The finding came to light in research conducted last year based on 154,514 students in grades 4-11 who were connected to school violence as victims, perpetrators and those who had witnessed such incidents.

Among the type of abuse, verbal assault was the most common form, with 69.1 percent of students being exposed to such abuse, followed by physical violence (27.3 percent), other bullying (21.3 percent), cyberbullying (13.9 percent) and sexual violence (9.5 percent).

While school violence stems from a slew of reasons, 1.7 percent, or 2,258 students who were previously school violence perpetrators, said they did it without a special reason or as a joke.

The student respondents called for enhanced educational programs designed to control their emotions and learn how to empathize and communicate with other peers.

The KEDI stressed the need for establishing school violence countermeasures in the future by analyzing the causes of such cases to prevent students from abusing students who are the same or similar age.