30 Children after starting school

Following the rules, 30 case series with 2116 patients with testicular torsion were collected and pooled. Of these, 1283 were timed in 6-hour bands. From pain onset, testis salvage was 97.2% at 0 to 6 hours, 79.3% at 7 to 12 hours, 61.3% at 13 to 18 hours, 42.5% at 19 to 24 hours, 24.4% at 25 to 48 hours, and 7.4% after 48 hours. In broader bands: 90.4% within 12 hours, 54.0% at 13 to 24 hours, and 18.1% after 24 hours. The authors conclude salvage can still happen past the usual 6 to 8 hour talk. So even if pain has gone on a long time, still get care — do not stay home because “it’s too late anyway.” In U.S. pediatric hospital data for 2000, 2003, and 2006, 2443 boys from 1 month to under 18 years had surgery for testicular torsion. Age of onset has two peaks: the first year of life, and early puberty

A multi-hospital trial enrolled 242 adolescents with idiopathic scoliosis who met criteria for bracing. Of these, 116 were assigned by lot and 126 chose for themselves whether to wear a brace. Success and failure were defined in advance: curve growing past 50 degrees was failure; still below that at skeletal maturity was success. Brace-group children were asked to wear at least 18 hours a day. Results were analyzed by initial assignment, whether or not they actually wore enough. Assigned brace group success 75%, assigned observation only 42% (OR 4.11, 95% CI 1.85–9.16), roughly 4 times the chance of success versus observation alone. Combining the lot-assigned and self-chosen groups: 72% versus 48% (after leveling baseline differences, OR 1.93, 1.08–3.46, still about 1.9 times). More hours worn per day meant higher success (P<0.001; this link is unlikely to be chance). The trial stopped early because the brace worked

34 studies with 284375 children and adolescents pooled. Peer bullying linked to suicidal thoughts, OR 2.23 (95% CI 2.10–2.37), about 2.2 times the chance versus not bullied. Another 9 studies, 70,102 people: bullying linked to suicide attempts, OR 2.55 (1.95–3.34), about 2.6 times. Results held across sex, age, and study quality. The link of cyberbullying to suicidal thoughts was stronger than offline bullying. Article 21 of the Regulations on School Protection of Minors (未成年人学校保护规定) lists five kinds of conduct: beating, kicking, slapping, grabbing/biting, shoving, pulling; insults, mockery, humiliating nicknames; snatching, forcing goods, or deliberate damage to property; malicious exclusion and isolation; fabricating facts online to defame or spread rumors. The same article says that when the side with an advantage in age, body, or numbers does these things willfully or maliciously and causes bodily harm, property loss, or mental harm, it may be found to be bullying. Article 22 requires staff who notice abnormal mood or bodily injury to inquire promptly and report. Article 23 requires the school, on receiving a report, to investigate at once, submit it to the bullying-governance body for finding and handling, and notify parents to take part. If bullying is found, educational discipline or a disciplinary sanction must follow. Serious bullying that violates public-security administration or may be a crime must not be concealed and must be reported promptly to public security and education authorities (nationwide, in force from 1 September 2021)

Grade-1 students in 12 Guangzhou primary schools were assigned by lot at school level (intervention schools 952 people, control schools 951, mean age 6.6 years). The intervention added one 40-minute outdoor activity class each school day and encouraged parents to take children out more after school. Over 3 years, new myopia was 30.4% in the intervention group (259 of 853 eligible) and 39.5% in controls (287 of 726). Difference −9.1 percentage points (95% CI −14.1 to −4.1, P<0.001); the true gap sits roughly between 4 and 14 percentage points fewer. Over 3 years, refractive progression (spherical equivalent change) was −1.42 D versus −1.59 D, a difference of 0.17 D (P=0.04). The intervention group progressed a little less. D is the unit for refractive power. Axial length (front-to-back eye length) growth did not differ between groups (P=0.07). Ten Core Knowledge Points for Preventing and Controlling Myopia in Children and Adolescents (防控儿童青少年近视核心知识十条) requires at least 2 hours of daytime outdoor activity a day, or 14 hours a week cumulative. It notes that even on cloudy days outdoor activity has a protective effect, and asks to avoid the early-afternoon hours of high heat and strong sun. Drug prevention of myopia also has lot-assigned trials. In Hong Kong, 474 children aged 4 to 9 without myopia were split into three groups and used eye drops once nightly for two years. With 0.05% atropine, myopia over two years was 28.4%; with placebo, 53.0%. With 0.01% atropine it was 45.9%, not different from placebo

Article 4 of Ten Core Knowledge Points for Preventing and Controlling Myopia in Children and Adolescents (防控儿童青少年近视核心知识十条) says in the original wording: “Infants and toddlers aged 0–3 shall not use phones, tablets, computers, or other screen electronic products; children aged 3–6 shall avoid contact with and use of phones, tablets, computers, and other screen electronic products as much as possible; for primary and secondary students, non-study screen use should not exceed 15 minutes per session, and cumulative daily use should not exceed 1 hour.” The same article states that “prolonged near use of electronic screen products readily depletes children’s hyperopia reserve and is an important cause of early and high rates of myopia in children and adolescents.” The 2018 implementation plan from the Ministry of Education and seven other departments gives parents the same requirements and adds “the younger the age, the shorter continuous use of electronic products should be.” Research evidence is much weaker: a systematic review took in 33 studies, 11 entered the pooled calculation, ages from 3 months to 33 years. Counting only phones and tablets, the odds ratio for myopia was 1.26 (95% CI 1.00 to 1.60, I²=77%). Combined with computers it was 1.77 (1.28 to 2.45, I²=87%). The authors conclude only “may be related,” and state that none of the 33 studies had a reliable measure of screen time

A systematic review and meta-analysis pooled studies before June 2019 into three degree bands: mild (−0.5 to −3.00 D), moderate (−3.00 to −6.00 D), high (≤−6.00 D, 600 degrees or more). Versus people without myopia, odds ratios for myopic macular degeneration were 13.57 (95% CI 6.18 to 29.79), 72.74 (33.18 to 159.48), and 845.08 (230.05 to 3104.34). Retinal detachment: 3.15 (1.92 to 5.17), 8.74 (7.28 to 10.50), 12.62 (6.65 to 23.94). Posterior subcapsular cataract: 1.56 (1.32 to 1.84), 2.55 (1.98 to 3.28), 4.55 (2.66 to 7.75). Open-angle glaucoma: mild 1.59 (1.33 to 1.91); moderate and high combined 2.92 (1.89 to 4.52). Odds ratios for visual impairment at age 60 and above: 1.71 (1.07 to 2.74), 5.54 (3.12 to 9.85), 87.63 (34.50 to 222.58). Ten Core Knowledge Points for Preventing and Controlling Myopia in Children and Adolescents (防控儿童青少年近视核心知识十条) says the same: 600 degrees or more is high myopia; in that group, rates of cataract, open-angle glaucoma, myopic macular disease, retinal detachment, myopic optic neuropathy, and other blinding eye diseases are clearly higher than in other groups, and “myopia can be prevented and controlled but is not reversible”

The 2021 Administrative Measures for Health Checks of Primary and Middle School Students requires all such schools to run one health check per year for every enrolled student. The physical exam covers the head, neck, chest, spine, limbs, skin, and lymph nodes, while the eye exam checks external eye condition, distance vision, and refractive errors (degree of myopia or hyperopia). The individual report issued to each student must include all test results, an overall assessment, and tailored health guidance. Overweight, obesity, malnutrition, spinal curvature issues, poor eyesight, and dental cavities are all designated as priority areas for follow-up. Education authorities are also required to keep records of students with health problems and follow up with them. All costs for these compulsory education health checks are paid by school budgets, with no extra charges for parents (issued nationwide in September 2021).

In 2022, the U.S. Preventive Services Task Force issued a recommendation statement advising that adolescents aged 12 to 18 be screened for major depressive disorder; this recommendation falls under Category B, meaning the evidence supporting it is moderate and the benefits are also moderate, making it worthwhile. For children aged 11 and under, there is insufficient evidence to support depression screening (an I statement, which indicates a lack of evidence and no formal recommendation). Likewise, evidence regarding both the benefits and harms of screening children and adolescents specifically for suicide risk is also insufficient (another I statement). The document emphasizes that suicide is the second leading cause of death among 10- to 19-year-olds, and that major depression in youth is closely linked to numerous later issues, including recurrent depressive episodes in adulthood and other mental disorders, as well as a heightened risk of suicidal thoughts, suicide attempts, and death by suicide. China’s “Ten Measures to Further Improve Mental Health Care for Primary and Secondary School Students” calls for establishing a three-tier support system: homeroom teachers, full- and part-time school counselors, and psychiatrists. Each student should undergo a mental health assessment, generally no more than once per academic year. The measures also stress the need to improve referral pathways to mental health specialists and reintegration processes after recovery. Additionally, they highlight the importance of leveraging the 12355 Youth Service Hotline and the 12356 Psychological Assistance Hotline (issued nationwide in October 2025).

A notice from the General Office of the State Administration for Market Regulation on its special enforcement campaign from November 2021 to March 2022 clearly reiterates that “under current medical technology, myopia cannot be cured.” It mandates strict legal action against any marketing of products aimed at preventing or controlling myopia in children and adolescents that employ misleading language like “recovery,” “restoration,” “reducing refractive error,” “curing myopia,” “myopia remedy,” or “repairing refractive error.” The notice also calls for intensified efforts to combat practices that misuse traditional Chinese medicine terminology or theories for deceptive advertising, as well as two specific types of false advertising: using patient testimonials or images to compare pre- and post-treatment outcomes, and making guaranteed claims regarding treatment safety or effectiveness. Additionally, e-commerce platforms are required to rigorously verify the qualifications of sellers offering medical devices such as eye-care instruments and other specialized products (nationwide).

The Notice on Further Strengthening Sleep Management for Primary and Secondary School Students stipulates that elementary students must get 10 hours of sleep daily, junior high students 9 hours, and high school students 8 hours. Elementary classes generally start no earlier than 8:20 a.m., and secondary school classes generally no earlier than 8:00 a.m. Schools are prohibited from requiring students to arrive at school early for mandatory educational activities. Elementary students generally go to bed no later than 9:20 p.m., junior high students no later than 10:00 p.m., and high school students no later than 11:00 p.m. Off-campus tutoring institutions must end no later than 8:30 p.m., and live online tutoring must end no later than 9:00 p.m. From 10:00 p.m. to 8:00 a.m. the next day, game services for minors are banned nationwide (issued March 2021). The Ten Measures for Further Strengthening Mental Health Work Among Primary and Secondary School Students contains several additional provisions. All schools are required to ensure students get at least 2 hours of combined physical activity per day, and the practice of offering 15-minute recess periods is encouraged. Students must not be ranked based on test scores, and repetitive, punitive homework assignments are strictly prohibited. It also encourages schools to set one “homework-free day” each week (nationwide, issued October 2025).

Article 16 of the Measures for the Administration of Primary and Secondary Student Enrollment Status (中小学生学籍管理办法) sets how leave works. The student takes leave on application by parents or other legal guardians. After the school confirms, it reports to the higher enrollment-status office for approval. On return the school must process the related steps promptly. One application for leave shall not exceed 1 year; if more leave is truly needed when it ends, a new application must be filed. During leave the school shall keep the enrollment status (student identity and place are held). Exact leave and return rules are made by provincial education authorities (nationwide, issued January 2025). Ten Measures to Further Strengthen Mental Health Work for Primary and Secondary Students (进一步加强中小学生心理健康工作十条措施) requires advancing referral of mental illness for medical care and return-to-school mechanisms after recovery, and guiding schools to make plans for sudden campus psychological crises

The “Ten Core Principles for Preventing and Controlling Myopia in Children and Adolescents” outlines how cycloplegic refraction works: it uses a cycloplegic agent to relax the focusing muscles before measuring refractive errors. This medical procedure is regarded as the gold standard for diagnosing myopia, providing the most accurate results. The drops themselves are safe for healthy eyes; side effects such as light sensitivity and blurred near vision are temporary and resolve after treatment ends. Once myopia is confirmed, timely corrective measures—such as wearing appropriate glasses—are essential. Proper glasses can correct vision and slow progression of the condition. For those whose vision is normal with glasses, preschool and elementary school children should be rechecked every 3–6 months and middle and high school students every 6–12 months; whether to change glasses is decided according to the situation. Regular refractive screenings are also recommended at ages 1–3, 4–6 and from age 7 on, to monitor hyperopia reserve (远视储备量, "farsightedness reserve"). (National guidelines issued July 2023)

This conclusion comes from 38 separate trials involving 7,924 children aged 5–16, all selected and pooled by Cochrane according to strict methodological standards. The studies compared children who received resin-based sealants with those who did not. For first permanent molars in the 5–10 age group, the odds ratio after 24 months was 0.12 (95% CI 0.08–0.19), meaning the risk of decay was roughly one-eighth that of untreated teeth. This result is based on seven trials with 1,548 participants randomly assigned and 1,322 actually examined; the overall evidence quality is rated as moderate. If the untreated control group shows 16% decayed surfaces within 24 months, the sealed group shows only 5.2% (range 3.13%–7.37%). When the control group rate reaches 40%, the sealed group still stays at 6.25% (3.84%–9.63%); at a 70% control rate, the sealed group remains at 19% (12.3%–27.2%). After 48–54 months the odds ratio remains low at 0.21 (0.16–0.28), indicating a risk roughly one-fifth that of untreated teeth. Authors conclude that resin sealants reduce cavity formation by 11%–51% compared with no sealants at 24 months. No adverse effects were reported in any of the four trials that monitored side-effects; however, there is insufficient evidence to determine whether glass-ionomer sealants perform better than other types.

A meta-analysis pooled 53 studies from 17 countries, 226,247 people. Prevalence of gaming disorder was 3.05% (95% CI 2.38–3.91; that is the credible range). Counting only studies with stricter sampling, 1.96%. Results differed widely across studies; 77% of the spread came from which questionnaire was used. Teen samples, low cutoff scores, and small samples all push the rate up. Another study took data from 7 game companies and linked 38935 players’ real play time over six weeks to self-reported happiness. Almost no evidence that play time affects happiness. The National Press and Publication Administration requires game firms to offer minors only 1 hour of service a day on Friday, Saturday, Sunday, and statutory holidays, from 20:00 to 21:00 (nationwide / international, from 2021)

A domestic survey covered 506 secondary schools in 7 provinces, 150822 students from grade 7 through grade 12. Past-year suicide attempts among boys: opposite-sex only 2.2%, same-sex only 6.9%, both sexes 12.2%. Girls: 3.1%, 8.9%, 10.9%. That is about 3 to 5.5 times peers who only like the opposite sex. Researchers subtracted age, academic pressure, family finances, and bullying. After that, for boys the two groups had OR 3.13 (95% CI 2.28–4.28) and 3.83 (2.85–5.14), about two to three times higher. A meta-analysis of 35 studies found OR 3.50 (2.98–4.12) for sexual-minority adolescents attempting suicide. A U.S. study interviewed 224 gay and bisexual youth aged 21 to 25 about family reactions in adolescence. Versus peers with almost no family rejection, high rejection had OR 8.4 for attempting suicide. In another study, parents who themselves tried to change the child’s sexual orientation: OR 3.08 (1.39–6.83) for the child’s suicide attempt. Parents who also sent the child to a therapist or religious figure: 5.07 (2.38–10.79) (China / multi-country / U.S.)

First, hitting. One meta-analysis counted only “open-hand spanking of the buttocks or limbs.” It pooled 75 studies, 111 effect sizes, 160927 children. Of 17 outcomes, 13 clearly linked to spanking, all in the bad direction. d is effect size; 0.2 is small, 0.5 medium. Childhood aggression d = 0.37 (95% CI 0.13–0.61, credible range). Externalizing problems 0.41 — hitting, breaking rules. Internalizing 0.24 — anxiety, depression. Mental health problems 0.53; poor relationship with parents 0.51; low self-esteem 0.15; poorer cognition 0.17. Physical abuse by parents 0.64. Adult antisocial behavior 0.36; adult mental health problems 0.24. Across 111 effect sizes, d = 0.33 (0.29–0.38). Whether the child obeyed on the spot was not clearly linked to spanking (d = 0.14, −0.19–0.47); that outcome had only 5 effect sizes. Another review looked only at before-and-after follow-up studies, 69 of them. Physical punishment stably predicted more later behavior problems; no link to any long-term good outcome was seen. Of 7 studies that counted how often hitting happened, 5 found more hitting linked to worse problems. Next, yelling. A U.S. study followed 976 two-parent families. At age 13, if parents often yelled, used foul language, or called the child stupid or lazy, misconduct and depressive symptoms both rose between ages 13 and 14. Whether parents were usually warm did not cancel the link. The reverse also held: children with more misconduct at 13 later got yelled at more. In law, parents must not use domestic violence against a child. Article 2 of the Anti-Domestic Violence Law (反家庭暴力法) lists forms of domestic violence: beating, binding, maiming, restricting personal liberty, and habitual insults and intimidation. Article 12 requires guardians to do family education in civilized ways. When parents infringe a child’s rights, residents’ and villagers’ committees must counsel and stop them, and report serious cases to public security. Public security, procuratorates, and courts that find this must admonish the parents and may order them to accept family-education guidance (nationwide)

Cochrane pooled 13 trials, 10 of them lot-assigned, 1078 parents. Children aged 3 to 12 all had behavior problems. Included programs met weekly or every other week, 1 to 2 hours each time, at least three sessions. Short ones ran 4 weeks straight; long ones 24 weeks. After the course, children’s behavior problems fell. Parent ratings SMD −0.53 (95% CI −0.72 to −0.34, credible range); independent raters −0.44 (−0.77 to −0.11). SMD and d are the same scale; 0.5 is medium. Parent mental health improved, −0.36 (−0.52 to −0.20). Harsh or negative parenting fell: parent ratings −0.77 (−0.96 to −0.59), independent −0.42 (−0.67 to −0.16). Authors say these are short-term effects. Another meta-analysis screened 346 lot-assigned trials; 60 measured hitting and yelling of children, across 22 countries. Hitting and yelling fell right after the course, d = −0.46 (−0.59 to −0.33). At 1 to 6 months −0.24 (−0.37 to −0.11). At 7 to 24 months −0.18 (−0.34 to −0.02), smaller later. Most of these data are parent-reported. There are domestic trials too. Shanghai randomized 81 parents; some took Triple P group classes. After the course, children’s adjustment problems and parents’ parenting and mood were better than waitlist parents, and still at 6 months. At a rural kindergarten, 191 caregivers took part; some self-studied online lessons plus two group discussions. Two weeks after finishing, self-reported child-abuse behaviors were about 33% lower than in those who only got a book (IRR 0.67). At three months, children’s behavior problems were also lower (d = −0.40). The Family Education Promotion Law (家庭教育促进法) requires parents to study family-education knowledge on their own. Primary and secondary schools and kindergartens may run parent schools and hold regular public-interest family-education guidance. Residents’ and villagers’ committees may run community parent schools. Governments at provincial level and above must run public-interest online parent schools and service hotlines. Family-education guidance bodies must not organize for-profit training (nationwide, in force from 1 January 2022)

Article 68 of the Law on the Protection of Minors (未成年人保护法) says no organization or individual may intervene in minors’ internet addiction in ways that harm minors’ physical or mental health. Both cases below have court judgments. The first was in Hefei, Anhui. In August 2017, parents of an 18-year-old boy signed an agreement with a special training school to treat internet addiction. School staff took him by force, locked him in a solitary room, and cuffed both hands to the window bars. They restricted food, water, and rest, and beat him. About 44 hours later the boy died. The appraisal concluded heat, restricted posture, lack of food and drink, and trauma caused water-electrolyte disorder and death. On 31 October 2018, Hefei Intermediate Court gave the first-instance judgment. The school head was convicted of intentional injury and unlawful detention and sentenced to 16 years. Four instructors got 1 year to 8 years and 6 months. On 28 December 2018, Anhui Higher Court upheld on second instance. The second-instance ruling stated the school had no approval from the relevant departments, and none of the defendants had teaching qualifications. The second was in Nanchang, Jiangxi. Yuzhang Academy opened in 2013 and was deregistered and closed in November 2017. While open, the school took some students into a “frustration relief room” for solitary confinement with dedicated guards, three to ten days each time. On 28 April 2023, Anyuan District Court in Pingxiang retried and gave first-instance judgment: five defendants constituted unlawful detention. Four were sentenced; Xinhua’s wording was “fixed-term imprisonment ranging from two years and ten months to eleven months.” Those four were also barred for a set period from education-related work; one was exempted from criminal punishment. Parents asked for tuition and travel costs back; the court did not support them (nationwide / Anhui / Jiangxi)

Cochrane in 2015 pooled 24 trials of school anti-sexual-abuse classes, 5802 students aged 5 to 18. Most classes taught a few things: safety rules, the body belongs to you, which parts are private. They also taught which touches are not OK, which secrets must not be kept, and whom to tell. Many classes stressed that if something happens it is not the child’s fault. First, whether children protect themselves. Researchers had people pretend to be strangers and lure children — 2 trials, 102 people. Those who took the class did protective moves with OR 5.71 (95% CI 1.98–16.51, credible range), about 5.7 times those who did not. Converted from the original: about 390 of 1000 without the class managed it, about 795 with the class. Next, knowledge. 18 trials, 4657 people, questionnaire scores SMD 0.61 (0.45–0.78); 0.5 is medium. At half a year still 0.69 (0.51–0.87). 3 studies, 795 people, looked at harm: children’s anxiety and fear did not rise or fall (SMD −0.08, −0.22 to 0.07). 3 studies, 1788 people, looked at whether children disclose. Disclosing that they had been sexually abused OR 3.56 (1.13–11.24), from about 4 per 1000 to about 14. But children in the same class and school are alike; after correcting for that, the difference was no longer clear (OR 3.04, 0.75–12.33). Evidence quality for all outcomes was moderate. Authors state that whether these classes truly reduce sexual abuse needs long follow-up. UNESCO and five other UN agencies issued sexuality-education guidelines in 2018. They recommend teaching names of body parts, including genitals, from ages 5 to 8. They also teach which body parts are private. If someone touches them and they feel uncomfortable, say “no,” leave, then tell a trusted adult. The guidelines state sexual abuse is never the victim child’s fault — including when done by acquaintances, trusted people, or family. People’s Daily’s anti-sexual-abuse handbook gives a memorable line: places covered by a vest and shorts, others must not look at or touch. Article 16 of the Law on the Protection of Minors (未成年人保护法) requires parents to give children safety education and raise self-protection awareness and ability. Article 40 requires schools and kindergartens to run age-appropriate sexuality education. If schools or kindergartens find sexual assault or harassment, they must not conceal it and must report promptly to public security and education. In 2020 the Supreme People’s Procuratorate and eight other departments built a mandatory-reporting system. People who must report include staff at schools, kindergartens, hospitals, childcare, residents’ and villagers’ committees, hotels, and similar. If in their work they find a child has been or is suspected to have been harmed, they must report to public security at once. Situations to report include: suspected abnormal injury to genitals or private parts; a girl under 14 suspected of sexual assault, pregnancy, or abortion. The reporter’s identity is kept confidential. If reporting leads to a dispute, the reporter bears no legal liability. In 2025 procuratorates prosecuted 42,873 people for rape, child molestation, and other sexual crimes against minors, 5.5% fewer than the prior year. That was 58.9% of prosecuted crimes against minors. Of cases prosecuted that year against minors, 3852 had leads from mandatory reporting, 7.1%. A 2025 opinion from the Supreme People’s Court and 15 other departments says acquaintance offenders make up a high share in such cases. Some young children lack awareness, and guardians pay little attention, so a child may be sexually abused without knowing it (nationwide / multi-country)

Article 72 of the Implementation Regulations of the Road Traffic Safety Law (道路交通安全法实施条例) says that on roads “driving a bicycle or tricycle requires full age 12.” The same article says “driving an electric bicycle or a motorized wheelchair for persons with disabilities requires full age 16.” Violation under Article 89 of the Road Traffic Safety Law (道路交通安全法) means a warning or a fine of 5 to 50 yuan; refusing the fine can mean the vehicle is seized. The fine is small; what matters is the bill after a crash. Article 1188 of the Civil Code (民法典) says when a minor causes harm to another, the guardian bears tort liability. If the child has their own property, pay from that first; any shortfall the guardian pays. Lianjiang County Court in Fujian decided one case. In May 2022, a child just turned 14 used the mother’s account to scan and rent a shared e-bike. They hit a person on an e-bike; the other side had grade-10 disability, and traffic police found the child fully at fault. The rental firm and insurer said the user agreement requires age 16 or above, so the child was not a lawful rider and they would not pay. The court ordered the child’s parents to pay about 187,000 yuan (exact figure 187017.83 yuan). Being hit while under age also costs. A Beijing judge wrote up a case: a 10-year-old riding a bicycle after school was hit by an e-bike into grade-10 disability; traffic police found the other side fully at fault. Article 1173 of the Civil Code says if the injured party was at fault for the harm, the tortfeasor’s liability may be reduced. On that basis the court found the child under 12 on the road and the guardian failing to stop it, and ordered the child’s side to bear a share of the loss. Injuries can also be worse. An Israeli trauma center admitted 337 children with traffic injuries from 2014 to 2016. Among those hurt on e-bikes, brain injury was 13%; on ordinary bikes, 3%. After other factors were included, the chance of more severe injury was about 2.6 times that of ordinary bikes (OR 2.56, 95% CI 1.1–5.88, credible range) (nationwide / Fujian / Beijing / Israel)

Concussion is a temporary disruption of brain function after a head hit; imaging usually shows nothing. A U.S. study followed 69 athletes with sport concussion, mean age about 15. The 35 taken out at once recovered in a mean 22.0 days. The 34 who kept playing with symptoms recovered in a mean 44.4 days (P=0.003; unlikely to be chance). Those who kept playing had 8.80 times the chance of recovery dragging past 21 days versus those taken out. A 2022 Amsterdam international sport-concussion meeting issued a consensus. It says loss of consciousness, seizures, unsteadiness, confusion, behavior change, or inability to remember events means immediate removal. Those people should not return to competition or training that day. The exception is when experienced medical staff check on the spot and confirm it is not from concussion. CDC guidance for parents and coaches is more direct: with suspected symptoms, leave at once, do not return that day, wait until a doctor says return is OK. It also says do not judge severity yourself — only medical staff can assess. It lists signals for emergency care at once: seizures; not recognizing people or places; repeated nausea and vomiting; odd behavior, growing confusion or agitation. Also growing sleepiness after passing out and not waking when called; slurred speech, weak or numb limbs. And headache that keeps getting worse without relief; unequal pupils or double vision (U.S. / multi-country)