Objective: To analyze and evaluate the comprehensiveness and reliability of the content related to comprehensive sexuality education in 16 subject curriculum standards in the current compulsory education system, and the feasibility and effectiveness of comprehensive sexuality education teaching practice. Methods: Based on the textbook analysis model, a curriculum standard analysis model was established, and the interpretive structure model was used to analyze and evaluate the content related to comprehensive sexual education in the curriculum standards of 16 subjects in the current compulsory education system, including Ethics and Rule of Law, Chinese, History, Mathematics, English, Japanese, Russian, Geography, Science, Physics, Chemistry, Biology, Information Technology, Physical Education and Health, Arts, Labor. Results: There were 7 subject curriculum standards including Ethics and Rule of Law, Chinese, English, Science, Biology, Information Technology, Physical Education and Health reflecting 5 core concepts and 12 themes of comprehensive sexuality education, and the most frequent core concept was Violence and Staying Safe and the Human Body and Development,as well as the most frequent theme was "Puberty". History, Mathematics, Japanese, Russian, Geography, Physics, Chemistry, Art and Labor didn t include content related to comprehensive sexuality education. The content related to comprehensive sexuality education in the curriculum standard of compulsory education presented three characteristics:it was closely related to the subject content, partial content was consistent with the teaching goal of the subject, and the content depth increased with the growth of grade. The comprehensiveness and reliability of comprehensive sexual education in the current compulsory education curriculum standards of China needed to be improved. Conclusion The comprehensiveness, reliability, feasibility and effectiveness of teaching practice of comprehensive sexuality education in 16 subject curriculum standards in the current compulsory education stage need to be improved.

Objective: To investigate the association between bedtime screen use and sleep health among fourth and fifthgrade primary school students, so as to provide evidence to support interventions for improving sleep quality. Methods: From April to June 2024, a survey was conducted among 4 232 fourth and fifthgrade students from nine primary schools in a district of Beijing. A selfdesigned questionnaire assessed bedtime screen use behavior and sleep health indicators. Generalized linear models and Logistic regression were used to analyze the associations. Results: Among the surveyed students, 28.3% reported bedtime screen use. Mean sleep duration every day was (9.31±0.90) hours on school days and (10.08±1.36) hours on weekends. Compared to nonusers, students with bedtime screen use exhibited every day: later bedtimes on school days (10.18 min delay, 95%CI=6.88-13.47) and weekends (22.09 min delay, 95%CI=17.33-26.85) (P<0.05); later weekend wake times (7.97 min delay, 95%CI=1.78-14.16, P<0.05); reduced sleep duration on school days (-9.82 min, 95%CI=-13.62 to -6.03) and weekends (-14.12 min, 95%CI=-20.24 to -8.00) (P<0.05); greater weekend-school day bedtime discrepancy (β=1.15, 95%CI=1.08-1.23, P<0.01). Additionally, they had lower odds of falling asleep within 20 minutes (OR=0.62, 95%CI=0.54-0.72), daytime alertness (OR=0.66, 95%CI=0.56-0.77), and subjective sleep satisfaction (OR=0.57, 95%CI=0.49-0.66)(P<0.01). Conclusions Bedtime screen use is associated with adverse effects on multiple dimensions of sleep health in primary school students. Reducing screen exposure before bed may help improve their sleep quality.