The reporter learned today from the Institute of Psychology of the Chinese Academy of Sciences that the blue book on mental health "China's National Mental Health Report (2019-2020)", which was investigated and compiled by the institute and published by the Social Sciences Academic Press, was recently released. Among them, the special report "The Inter-annual evolution of adolescent mental health status in 2009 and 2020" by examining the evolution trend of adolescent depression and sleep status in more than 10 years found that the detection rate of depression in adolescents remained stable, and the phenomenon of sleep deprivation became increasingly serious: 95.5 percent of elementary school students, 90.8 percent of middle school students and 84.1 percent of high school students fell short of the required amount of sleep.

Chen Zhiyan, deputy editor-in-chief of the blue book and a professor at the Institute of Psychology of the Chinese Academy of Sciences, said that there are two main aspects of teenagers' lack of sleep: First, the proportion of teenagers who sleep less than eight hours on school days has increased by 1 percentage point. In 2009, 47.4 percent of teens slept eight hours or more on school days, compared with 46.4 percent in 2020. The average amount of sleep teens will get in 2020 will be 7.8 hours, 0.3 hours less than in 2009.

Analysis by school segment showed that 95.5% of primary school students slept less than 10 hours a day, with an average of 8.7 hours; 90.8% of middle school students sleep less than 9 hours a day, with an average of 7.6 hours. 84.1% of high school students sleep less than eight hours a day, with an average of 7.2 hours.

Second, the sleep duration on school days showed a downward trend with the increase of grade, and the phenomenon of making up sleep on weekends showed a school division. Compared with more than 10 years ago, the sleep duration of adolescents in all school stages in 2020 shows a downward trend, and the average sleep duration of primary and middle school days is reduced by about 40 minutes, and the average sleep duration of senior one and senior two is reduced by 10 to 20 minutes. The average sleep duration of elementary school students on weekends decreased by about 12 to 25.2 minutes, by about 20 minutes in grade one and two, and by 40.2 to 51.3 minutes in grade three and high school.

Chen Zhiyan said that compared with more than 10 years ago, the mental health status of teenagers is stable and has declined. The detection rate of depression remained stable, and the detection rate of mild depression increased slightly. However, the percentage of adolescents with suicidal ideation in 2020 is 6.2 percentage points higher than in 2009, especially girls, 10.4 percentage points higher than in 2009.