Younger students experience school bullying more frequently than older children, and boys are affected by the problem more than girls, a new survey has found.

The 21st Century Education Research Institute, a think tank in Beijing, interviewed more than 1,000 students from 12 schools in the capital: four primary schools, four junior middle schools and four high schools.

It found almost half had been intentionally bumped into or knocked down by a classmate, while about 6 percent said they are physical bullied on a daily basis.

The findings also suggested that students at standard schools experience more bullying than those at top institutions, with children from impoverished families more likely to be bullied.

Being bullied can have an adverse effect on a child's personal development and academic performance, according to Zhou Jinyan, a researcher at Beijing Normal University's Institute of Educational Economics.

"Children who have been bullied find it hard to trust others," said Zhou, who led the study. "They lack self-confidence and often feel anxious, angry or depressed, affecting their ability to control their own life."

In recent years, there have been frequent reports of bullying incidents at schools in China, attracting widespread attention.

Zhou suggested three ways to resolve the problem: improving communication between teachers and students; establishing a more harmonious atmosphere among children; and ensuring parental participation in children's education.