[← Back to table of contents](../../README.md) # 1. Do not die early This section covers three things: deaths from accidents and injuries such as road crashes, fires, and poisoning; a few vaccines and screenings backed by the strongest evidence; and which bodily signals mean you should get checked. Figures in the Benefit field come from randomized trials, long-term cohort studies, or official statistics. Figures in the Cost field are the author's rough estimates from market prices, for comparison only—not for citation. ### 1. Always wear seat belts, both front and back - Cost: No cost at all. It only adds about 2 seconds to every trip. - In plain terms: Wearing a seat belt in the front seat cuts the risk of dying in a crash by roughly half. For drivers and passengers in light trucks, the reduction is about 60%. Among U.S. crash victims in 2022 whose seat belt use was documented, half were not wearing one. - Benefit: According to NHTSA estimates, seat belts lower the risk of fatal injury for front‑seat occupants of cars by 45% and for those in light trucks by 60%. In 2022, half of the U.S. fatalities in passenger cars had no recorded seat belt use. The World Health Organization states that seat belts can reduce the risk of death inside a vehicle by up to 50%. WHO also estimates that in 2021, 248,099 people died in road crashes in China, which translates to 17.4 deaths per 100,000 people. - Evidence grade: A - Sources:NHTSA (2024). Occupant Protection in Passenger Vehicles: 2022 Data (DOT HS 813 573). ; WHO (2025). Road traffic injuries fact sheet. ; WHO GHO RS_196/RS_198 (China, 2021). - Notes: Seat belts must be worn in the back seat as well. In the same report, 60% of rear‑seat occupants killed in crashes were not wearing belts. The 45% and 60% figures are NHTSA estimates derived from crash‑database analysis (Kahane 2015), not from randomized trials. The Chinese death toll cited by WHO is a projection and is several times higher than official police statistics; the two figures cover different populations, so only the WHO estimate is used here. ### 2. Wearing a helmet and fastening the strap while riding motorcycles or e-bikes - Cost: A helmet costs between 100 and 300 yuan. It takes just 5 seconds to put on each time. - In plain terms: Wearing a helmet and fastening the strap properly reduces a motorcyclist’s risk of dying in an accident by roughly 40%. The chance of suffering a head injury drops by about 70%. The strap must be tightened; a helmet that simply hangs loosely on the head does not count as being worn. - Benefit: Cochrane pooled data from multiple studies. For motorcyclists wearing helmets, the risk of death fell by 42%. The original odds ratio was 0.58, with a 95% confidence interval ranging from 0.50 to 0.68. Head injuries were reduced by 69% (odds ratio 0.31; 95% CI 0.25–0.38). - Evidence grade: A - Sources:Liu BC 等 (2008). Helmets for preventing injury in motorcycle riders. Cochrane Database of Systematic Reviews. - Notes: The helmet strap must be fastened securely. A helmet left hanging on the handlebars does not count as being worn. The figures above apply specifically to motorcycles. For e-bikes, no direct studies exist, but the mechanics of head injury in a crash remain the same. ### 3. Install smoke alarms; those heating with coal or gas in winter should also add a carbon monoxide alarm - Cost: A smoke alarm costs between 30 and 100 yuan. A carbon monoxide alarm costs between 50 and 150 yuan. After installation, the batteries need to be replaced once a year. - In plain terms: A properly functioning smoke alarm can cut the risk of dying in a home fire by roughly 60%. Forty percent of fire victims are asleep at the time, so they won’t wake up just from the smell of smoke. For anyone heating their home with coal or gas during winter, adding a carbon monoxide alarm is essential. In China, 11,500 people died from carbon monoxide poisoning in 2018; 70% of those deaths occurred at home during the three winter months. - Benefit: A study in North Carolina examined homes that had experienced fires versus those that hadn’t. It found that having a working smoke alarm lowered the death risk by about 60%. The odds ratio was 0.39, with a 95% confidence interval ranging from 0.18 to 0.83. Between 2018 and 2020, 24% of fatal residential fires in the U.S. happened in homes without smoke alarms, and 41% of victims were asleep when the fire started. In 2018, China reported 11,523 deaths from carbon monoxide poisoning; of these, 72.59% occurred at home in December, 67.42% in January, and 66.48% in February. - Evidence grade: B - Sources:Marshall SW 等 (1998). Fatal residential fires: who dies and who survives? JAMA. ; USFA (2022). Fatal Fires in Residential Buildings (2018-2020), Topical Fire Report Series 22(2). ; You J 等 (2020). Number of Deaths due to Carbon Monoxide Poisoning by Month and by Place of Death — China, 2018. China CDC Weekly. - Notes: This grade is assigned because only one study exists on smoke alarms; it compared past fire incidents in various homes rather than using a randomized trial design. No research has shown that carbon monoxide alarms reduce mortality rates. The reported benefits are inferred from the fact that most poisoning deaths happen at home during winter. ### 4. Replace gas hoses and stoves when they reach their expiration date; never modify the piping yourself, and you may decline any unsolicited sales pitches from gas companies - Cost: A compliant gas hose costs only a few dozen yuan. Stoves should be replaced every few years; during replacement, check whether they’ve passed their expiration date. - In plain terms: A compliant gas hose costs just a few dozen yuan. Replacing it when it expires is a user obligation clearly stated in the “Regulations on Urban Gas Management.” The same regulations explicitly forbid users from modifying piping or removing gas meters on their own. Additionally, the regulations state that gas companies cannot require customers to purchase specific products or services. Therefore, you may freely decline any sales pitches claiming that replacement is mandatory. - Benefit: The regulations designate “promptly replacing gas appliances and connecting hoses that have been phased out by the state or have exceeded their service life” as a user obligation; this means you must replace any stove or hose that has reached its expiration date or been discontinued. The same regulations also classify “unauthorized installation, modification, or removal of indoor gas facilities and metering devices” as prohibited actions, which includes any DIY attempts to alter piping or remove gas meters. Furthermore, the regulations explicitly forbid gas operators from mandating that users purchase particular products or accept specific services. - Evidence grade: A - Sources:国务院 (2010). 城镇燃气管理条例（国务院令第 583 号）第二十七条：「燃气用户应当遵守安全用气规则，使用合格的燃气燃烧器具和气瓶，及时更换国家明令淘汰或者使用年限已届满的燃气燃烧器具、连接管等」；第二十八条禁止行为含「（一）擅自操作公用燃气阀门」「（二）将燃气管道作为负重支架或者接地引线」「（四）擅自安装、改装、拆除户内燃气设施和燃气计量装置」；第二十条燃气经营者不得「（六）要求燃气用户购买其指定的产品或者接受其提供的服务」；第二十九条用户可就收费、服务向燃气管理等部门投诉，「有关部门应当自收到投诉之日起15个工作日内予以处理」. ；深圳市住房和建设局 (2024). 安全用气小知识（二）：「立即关闭家里的燃气总阀门」「迅速开门、开窗进行通风」「一定不要开、关家里的电灯、抽油烟机等电器」「人员应该迅速撤离，转移到安全的地方，并且及时拨打燃气公司的报警电话」. ；张家港市应急管理局 (2024). 燃气安全使用知识：「不要情急之下打开排气扇进行通风」「应远离现场之后才能打电话求助」. - Notes: Some individuals pose as gas inspectors and, after performing a check, attempt to sell self-closing valves and alarms. However, Article 20, Clause 6 of the regulations bars gas companies from requiring you to buy their designated products; you may decline such offers or even file a complaint. If you detect a gas odor, first shut off the main gas valve; in the case of bottled gas, close the cylinder valve as well. Then open doors and windows to ventilate the area, but avoid using exhaust fans. Do not turn on or switch off any electrical appliances—including lights and range hoods—and refrain from using lighters. After that, leave the premises immediately and call the gas company’s emergency line from a safe location. Carbon monoxide poisoning is a separate issue; refer to Section 13 for details. ### 5. Do not pick, buy, or eat wild mushrooms; any “folk tricks” for identification are useless - Cost: No expense involved. The hard part is giving up a seasonal delicacy. - In plain terms: In 2025 alone, there were 828 cases of mushroom poisoning across China, affecting 2,165 people, with 13 fatalities. That same year, 34 previously unknown poisonous mushroom species were identified. Myths such as using a silver needle to test for toxicity, assuming mushrooms safe if insects eat them, or that only brightly colored varieties are toxic are all false. - Benefit: The Chinese CDC investigated 828 mushroom poisoning cases in 2025 involving 2,165 individuals; the mortality rate was 0.6%. From 2019 to 2024, annual cases ranged from 276 to 676, with mortality rates between 0.87% and 2.86%. In 2025 alone, 138 poisonous mushroom species were identified, including 34 new ones never documented before as causing poisoning. - Evidence grade: A - Sources:Mushroom Poisoning Outbreaks — China, 2025. China CDC Weekly (2026)：「In 2025, China CDC investigated 828 mushroom poisoning incidents across 27 provincial-level administrative divisions (PLADs), affecting 2,165 individuals and causing 13 deaths - a case fatality rate of 0.6%, the lowest of the past six years. In total, 138 poisonous mushroom species were identified, including 34 newly recorded in poisoning incidents in China.」「From 2019 to 2024, the annual number of incidents ranged from 276 to 676, and the case fatality rate ranged from 0.87% to 2.86%.」；同刊 2024 年度报告 - Notes: If you accidentally eat poisonous mushrooms, induce vomiting immediately and then go to the hospital with any remaining mushrooms or photos of them. There are several types of mushroom poisoning, and identifying the exact species is crucial for proper treatment. New poisonous species are discovered each year, so the assumption that “local people can recognize them” is unfounded. Claims such as silver needle testing, cooking with garlic, insect consumption indicating safety, or vivid colors signaling toxicity are all incorrect. ### 6. Electric bicycles must not be pushed into stairwells, elevators, or charged indoors - Cost: No direct cost. The tricky part is having to walk a few dozen meters each time to reach the designated charging stations downstairs. - In plain terms: Pushing an electric bike into a stairwell, elevator, or charging it at home is strictly prohibited under the Ministry of Emergency Management’s regulations on fire safety in high-rise residential buildings. Those who violate the rules face fines of $500–$1,000 for individuals and $2,000–$10,000 for businesses. Even these fines are the least of the concerns — the real danger is that a fire could block your only escape route. - Benefit: The regulations explicitly forbid parking or charging electric bikes in public lobbies, hallways, stairwells, or near emergency exits of high-rise buildings. Noncompliance results in the same fines mentioned above. - Evidence grade: A - Sources:应急管理部 (2021). 高层民用建筑消防安全管理规定（应急管理部令第 5 号，第三十七条、第四十七条）. ；应急管理部 (2023). 关于政协第十三届全国委员会第五次会议第00969号提案答复的函：「2021年，全国共接报电动自行车火灾1.8万起，造成65人死亡、222人受伤，直接财产损失达2.21亿元，其中发生在建筑物内3782起，造成60人死亡、175人受伤」. ；应急管理部 (2025). 2025年1月15日新闻发布会：「火灾起数同比下降42.2%，伤亡人数下降超过90%」. - Notes: Avoid buying modified batteries or generic chargers, and never leave a battery charging unattended overnight. Lithium-ion batteries can ignite within seconds of catching fire, producing highly toxic smoke. A fire in a stairwell essentially blocks your only way out. In 2021, there were 18,000 electric bike-related fires nationwide, causing 65 deaths; 3,782 of those occurred inside buildings, claiming 60 lives, most of whom were indoors. Following stricter enforcement in 2024, fire incidents dropped 42.2% year-on-year, with casualties falling by over 90% — exact figures for 2024 have not been released. ### 7. Measuring blood pressure and taking meds to reach target levels - Cost: An electronic sphygmomanometer costs 100–200 RMB. Each measurement takes 1 minute. Most antihypertensive drugs cost just a few to dozens of RMB per month. The hard part is keeping the medication regimen even when there are no symptoms. - In plain terms: For every 10 mmHg drop in blood pressure, the risk of major cardiovascular problems falls by 20%, stroke risk drops 27%, heart failure risk drops 28%, and overall mortality risk declines by 13%. Among Chinese adults aged 35–75, 44.7% have hypertension, but only 7.2% have their blood pressure under proper control. - Benefit: Data from 123 clinical trials involving over 610,000 participants shows that a 10 mmHg reduction in systolic blood pressure lowers the incidence of major cardiovascular events by roughly 20%. The relative risk is 0.80, with a 95% confidence interval of 0.77–0.83. Systolic blood pressure is the higher of the two readings taken during a measurement. Stroke risk drops by 27% (RR 0.73), heart failure risk drops by 28% (RR 0.72), and overall mortality drops by 13% (RR 0.87, 95% CI 0.84–0.91). A screening program in China involving 1.7 million adults aged 35–75 found that 44.7% had hypertension; of these, 44.7% were aware of their condition, 30.1% were receiving treatment, and only 7.2% had their blood pressure under control. - Evidence grade: A - Sources:Ettehad D 等 (2016). Blood pressure lowering for prevention of cardiovascular disease and death: a systematic review and meta-analysis. Lancet. ; Lu J 等 (2017). Prevalence, awareness, treatment, and control of hypertension in China (China PEACE Million Persons Project). Lancet. - Notes: Start by getting your blood pressure measured at least once. Fewer than 1 in 10 Chinese adults with hypertension manage to keep their levels under control, so this single measurement is one of the most cost-effective actions you can take as outlined in this book. There is still some debate over what exact target level (130 or 140 mmHg) is ideal, but there is no dispute that knowing you have hypertension and taking steps to lower it is highly beneficial. ### 8. After age 35, anyone who is overweight should get a fasting blood glucose test; if the result is normal, repeat it every three years - Cost: A fasting blood glucose test costs just a few dozen yuan. Testing for glycated hemoglobin is a bit pricier, still only a few dozen yuan. All it takes is one blood draw at a clinic. - In plain terms: For just a few dozen yuan, a single blood test can detect prediabetes even when there are absolutely no symptoms at all. Official US screening guidelines recommend this test for anyone aged 35 to 70 who is overweight or obese. If the test comes back normal, they should repeat it every three years. - Benefit: The US Preventive Services Task Force is the official body that issues screening recommendations in the US. Its current guidance states that adults aged 35 to 70 who are overweight or obese — even with no symptoms at all — should be screened for prediabetes and type 2 diabetes. Overweight is defined as a BMI of 25 or higher, while obesity means a BMI of 30 or higher. This recommendation is rated as a Grade B. The Task Force also explicitly notes: “It is reasonable to screen adults with normal blood glucose levels for prediabetes every three years.” - Evidence grade: A - Sources:US Preventive Services Task Force (2021). Screening for Prediabetes and Type 2 Diabetes. ：「at a lower BMI (≥23) if the patient is Asian American」；国家卫生健康委办公厅 (2024). 居民体重管理核心知识（2024 年版）释义：「根据《成年人体重判定》（WS/T 428-2013）行业标准……24.0≤BMI＜28.0 为超重，BMI≥28.0 为肥胖」. - Notes: Having a prediabetes diagnosis does not mean you must start taking medication right away. Many people can fully reverse this condition simply by making lifestyle changes. In China, only a small fraction of adults are aware they have diabetes; most only find out after developing complications. ### 9. Don’t speed or drive after drinking - Cost: There’s no direct cost. Driving a bit slower adds just a few minutes to each trip. The hard part is drinking less at social gatherings. - In plain terms: On average, for every 1% increase in speed, the chance of a fatal crash rises by roughly 4%. There is no “safe” level of alcohol consumption when it comes to driving; even very low blood alcohol concentrations already raise the risk of accidents. - Benefit: According to the World Health Organization (WHO), a 1% rise in average speed translates to a 4% increase in the likelihood of fatal crashes. The risk of a fatal crash also climbs steadily as blood alcohol concentration rises, even at very low levels. - Evidence grade: B - Sources:WHO (2025). Road traffic injuries fact sheet. - Notes: The 1% and 4% figures linking speed to fatalities come from accident modeling rather than controlled trials. For alcohol and driving, WHO only provides a general trend without specific numerical values. This section does not verify any original research on exactly how much drinking raises risk. ### 10. Use a car seat for children under 4, don’t hold them in your arms - Cost: A seat costs between 300 and 2,000 yuan and lasts several years. It adds about one minute to each trip to buckle the child in. - In plain terms: For infants under one year old, using a car seat cuts the risk of a fatal injury in a crash by roughly 70%. For children aged 1 to 4, the risk drops by about half. Holding a child in your arms provides no such protection; in a sudden stop you simply cannot keep them secure. - Benefit: According to the U.S. National Highway Traffic Safety Administration (NHTSA), car seats lower the risk of fatal injury for infants under one year old by 71% and for children aged 1 to 4 by 54%. The World Health Organization reports a similar 71% reduction in infant deaths. - Evidence grade: A - Sources:NHTSA (2024). Occupant Protection in Passenger Vehicles: 2022 Data (DOT HS 813 573). ; WHO (2025). Road traffic injuries fact sheet. - Notes: Follow the manufacturer’s instructions to install the seat correctly; a faulty installation offers no protection. Infants under one year must be placed rear‑facing. These figures are based on official U.S. crash data. ### 11. Install window guards and balcony barriers if you have kids at home; screen windows do not count as protection - Cost: A set of window guards or child safety locks costs just a few dozen yuan to install, and the whole process takes only ten minutes. - In plain terms: These window guards cost only a few dozen yuan each. New York City once offered free window guards to high-risk households and provided on-site guidance; as a result, child fall incidents reported in one borough dropped by half over three years. Eventually, New York even passed a law requiring landlords to install such guards in rental units with kids under 10. Screen windows, however, can be easily pushed open — they do not provide any real protection. - Benefit: Since 1972, New York City has run a program called “Kids Can’t Fly,” which distributes free window guards in high-risk neighborhoods and offers on-site safety guidance. Between 1973 and 1975, child fall incidents reported in the Bronx dropped by 50%. Following this success, New York updated its health code to make it mandatory for landlords to install window guards in all apartments housing kids under 10 years of age. - Evidence grade: B - Sources:Spiegel CN, Lindaman FC (1977). Children can't fly: a program to prevent childhood morbidity and mortality from window falls. American Journal of Public Health：「Significant reduction in falls resulted, particularly in the Bronx, where reported falls declined 50 percent from 1973 to 1975」，1976 年纽约市卫生法典修订「to require that landlords provide window guards in apartments where children ten years old and younger reside」. ；(2021). Unintentional Window Falls in Children and Adolescents. Academic Pediatrics：2007 年 1 月至 2017 年 8 月全国电子伤害监测系统 38,840 例急诊就诊，「The majority of falls occurred in children under the age of 6 and were related to falls from a second story or below」. - Notes: Avoid placing beds, sofas, boxes, or any other objects near windows or balconies that kids might climb onto. Screen windows only keep mosquitoes out; they can be easily pushed open, so never rely on them as a safety barrier. This protection is needed even on lower floors: most child falls recorded in U.S. data actually occur on the second floor or even lower. ### 12. Keep young children in sight near water; wear life jackets when boating or swimming - Cost: Life jackets cost between 50 and 200 yuan. Additionally, parents must dedicate constant attention to watching their children. - In plain terms: Wearing a life jacket while in the water cuts the risk of drowning to roughly half compared to not wearing one. Drowning remains the leading cause of death among children aged 1–14 in China. The drowning mortality rate in rural areas is roughly twice that in cities. - Benefit: Research using U.S. Coast Guard data compared similar groups of people. For individuals who fell overboard while boating recreationally, wearing a life jacket lowered their drowning risk by about half. The unadjusted RR was 0.51, with a 95% CI of 0.35–0.74. In China, the drowning mortality rate among people under 20 fell from 6.60 per 100,000 in 2013 to 3.28 per 100,000 in 2021; rural rates remained roughly twice those in cities. Drowning continues to be the top cause of death for children aged 1–14. In 2021, drowning accounted for 31.1% of all injury-related deaths among those aged 0–19, while road traffic injuries accounted for 27.9%. - Evidence grade: A - Sources:Cummings P 等 (2011). Association between wearing a personal floatation device and death by drowning among recreational boaters. Injury Prevention. ; Li Z 等 (2023). Unintentional Drowning Mortality Among Individuals Under Age 20 — China, 2013–2021. China CDC Weekly. ; Zhou J 等 (2024). Injury Mortality of Children and Adolescents Aged 0–19 Years — China, 2010–2021. China CDC Weekly. - Notes: The Grade A rating applies only to the protective effect of life jackets. The practice of keeping children within sight is widely accepted but only qualifies for a Grade C rating due to lack of randomized trials; no such trials are expected in the future. In China, drowning deaths occur most often in rural areas during summer months, and among males aged 15–19. ### 13. Exercising balance and leg strength for people over 60, plus home modifications - Cost: Aim to practice balance exercises two to three times per week, each session lasting 30 minutes — activities like Tai Chi work well. Installing non-slip mats, handrails, and night lights in bathrooms and stairways costs anywhere from a few dozen to several hundred yuan. The real challenge is maintaining this routine over the long term. - In plain terms: Doing balance exercises such as Tai Chi two or three times weekly can cut the overall number of falls among older adults by roughly 23%. It also reduces the proportion of people who have fallen at least once by about 15%. Adding simple home modifications — like anti-slip mats and handrails — can lower fall rates by another 20% or so. Falls are the leading cause of injury-related deaths among Chinese seniors aged 65 and above; alarmingly, over half of all falls happen right at home. - Benefit: Cochrane analyzed 108 separate trials involving 23,407 participants. Collectively, these studies show that regular exercise lowers fall rates among older adults by 23%. The relative risk of falls dropped to 0.77, with a 95% confidence interval ranging from 0.71 to 0.83. The proportion of individuals experiencing at least one fall also fell by 15% (relative risk 0.85). Professional home safety assessments and modifications further reduced fall rates by roughly 20% (RR 0.81; 95% CI 0.68–0.97). Practicing Tai Chi specifically lowered fall risk by about 29% (RR 0.71). In China, falls remain the top cause of injury-related mortality for seniors over 65; data from 2018 indicates that 55.97% of all falls among this age group occur at home. - Evidence grade: A - Sources:Sherrington C 等 (2019). Exercise for preventing falls in older people living in the community. Cochrane Database of Systematic Reviews. ; Gillespie LD 等 (2012). Interventions for preventing falls in older people living in the community. Cochrane Database of Systematic Reviews. ; Lu Z 等 (2021). Characteristics of Falls Among Older People — China, 2018. China CDC Weekly. - Notes: This recommendation applies to seniors aged 60 and above who live independently at home rather than in nursing homes. The studies referenced here focus on the total number of falls, not on actual mortality rates. It’s important to note that the path from a fall to a hip fracture — and ultimately death — can be very short for older adults. ### 14. Get tested for hepatitis B markers; if no antibodies, get vaccinated - Cost: The test costs just a few dozen yuan per person. For adults lacking antibodies, three doses of the hepatitis B vaccine cost between 100 and 300 yuan total, to be completed within six months. - In plain terms: The test itself is very inexpensive. In Qidong’s 30‑year follow‑up study, infants who received the hepatitis B vaccine at birth had an 84% lower risk of developing primary liver cancer and a 72% lower rate of carrying the hepatitis B virus compared to unvaccinated peers. Adults found to have no antibodies should receive three vaccine doses over six months at a cost of roughly 100–300 yuan. - Benefit: This Qidong trial used group randomization rather than individual assignment and was tracked for three decades. Vaccination at birth cut primary liver cancer incidence by 84% (95% CI 23%–97%). The prevalence of hepatitis B surface antigen (HBsAg) fell by 72% (95% CI 68%–75%), reflecting a comparable drop in the proportion of people carrying the virus. Nationwide in China, HBsAg prevalence dropped 52% between 1992 and 2014, and fell 97% among children under five. - Evidence grade: A - Sources:Qu C 等 (2014). Efficacy of neonatal HBV vaccination on liver cancer and other liver diseases over 30-year follow-up of the Qidong hepatitis B intervention study. PLoS Medicine. ; Cui F 等 (2017). Prevention of Chronic Hepatitis B after 3 Decades of Escalating Vaccination Policy, China. Emerging Infectious Diseases. - Notes: This recommendation applies to adults born before 1992 who never received the vaccine or whose antibodies have waned. The 84% cancer‑risk reduction pertains only to those immunized at birth; adolescents vaccinated later saw only a 21% reduction in virus carriage. For adults, the main goal is preventing new infection, not achieving the same cancer‑prevention benefit. Vaccination offers no protection to people already infected; they must see a hepatologist regularly. Infection is confirmed when the hepatitis B surface antigen (HBsAg) test result is positive. ### 15. If you get pricked by a nail or splinter, or if a wound gets dirty with soil, seek treatment the same day and ask whether a tetanus shot is needed - Cost: Seeing a doctor and having the wound treated typically costs a few dozen yuan. If a shot is recommended, the vaccine or immunoglobulin will add another few dozen to several hundred yuan. - In plain terms: Once tetanus sets in, about 1 out of every 10 people dies. The risk is highest for deep wounds or wounds contaminated with dirt. If a wound is dirty and it’s been 5 years or more since your last tetanus shot, you’ll need a booster. Getting treated the same day costs only a few dozen yuan — don’t wait until the wound starts swelling. - Benefit: In the U.S., roughly 1 out of every 10 tetanus cases ends in death. Deep wounds and those exposed to dirt carry an even higher risk. China’s 2024 treatment guidelines classify wounds into two categories. Wounds treated within 6 hours that aren’t dirty and haven’t been exposed to feces, animal saliva, or soil are considered low‑risk. Wounds treated later, or those contaminated with such substances, as well as puncture wounds, avulsions, crush injuries, burns, frostbite, or wounds containing foreign bodies, are deemed high‑risk. If you’ve received three or more tetanus shots and the most recent one was less than 5 years ago, no further dose is needed. For high‑risk wounds, a booster is required if it’s been 5–10 years since your last shot; after 10 years, a booster is mandatory regardless of risk level. If you’ve never completed the three‑dose series or can’t recall when you last got a shot, you’ll need to finish the series and, for high‑risk wounds, also receive passive immunization (an injection of immunoglobulin or antitoxin that delivers antibodies directly). - Evidence grade: B - Sources:美国疾病控制与预防中心. 破伤风：「Tetanus bacteria can get into someone's body through broken skin, usually through injuries.」「Tetanus can lead to death (1 in 10 cases in the United States are fatal).」「People who didn't complete the primary series or who aren't up to date with their 10-year tetanus booster shots are also at increased risk.」「Vaccination also helps prevent tetanus in people with wounds, depending on their tetanus vaccination history.」；国家卫生健康委办公厅 (2024). 关于印发非新生儿破伤风诊疗规范（2024 年版）的通知（国卫办医急函〔2024〕381 号，风险分级见附件第 16 页，表 4 见第 20 页）. ；附件 PDF（扫描件）. - Notes: At the hospital, let the doctor make the decision — don’t guess on your own, and don’t hesitate to ask questions. Not every wound requires a tetanus shot; the doctor will assess the wound category and your vaccination history before deciding. The idea that “one shot in childhood provides lifelong protection” is a myth. If a wound is dirty, a booster is needed after 5 years, so try to recall when you last received a tetanus shot before heading to the clinic. ### 16. The earlier women get the HPV vaccine, the better - Cost: Domestic bivalent vaccines cost around 300 RMB per dose, while imported 9‑valent vaccines cost about 1300 RMB per dose. A total of 2–3 doses are needed, and each visit takes half a day. - In plain terms: Data from 1.67 million Swedish women show that those who received the HPV vaccine before age 17 have only about one‑eighth the risk of developing invasive cervical cancer compared to unvaccinated women. For women vaccinated between 17 and 30, the risk is roughly half that of non‑vaccinated peers. Therefore, getting vaccinated earlier offers the greatest benefit. - Benefit: Swedish research on 1.67 million women found that vaccinated individuals have a much lower incidence of invasive cervical cancer. Before age 17, vaccination reduces risk by roughly 88% (IRR 0.12, 95% CI 0.00–0.34). Vaccination between 17 and 30 still lowers risk by about 53% (IRR 0.47, 95% CI 0.27–0.75). - Evidence grade: A - Sources:Lei J 等 (2020). HPV Vaccination and the Risk of Invasive Cervical Cancer. New England Journal of Medicine. - Notes: The greatest benefit is seen when vaccination occurs between ages 9 and 14. Even for women aged 17–30, risk is still reduced by more than half. After age 30, the protective effect gradually diminishes. Vaccinated women still need regular cervical cancer screening; the vaccine does not replace screening — see item 18 for screening guidelines for women over 30. ### 17. Breast cancer screening for women: mammograms every two years starting at age 40 - Cost: A mammogram costs around 200–300 yuan each time. Many regions also offer free screening programs. Each screening takes about half a day. - In plain terms: For women aged 40 to 74, having a mammogram every two years is a clear recommendation in official US screening guidelines. For women over 75, and for those with dense breast tissue who need extra ultrasound or MRI scans, there is currently insufficient evidence to support such screening. If a health check package includes these extra tests at an extra charge, they are not necessary. - Benefit: The US Preventive Services Task Force is the official body that issues screening recommendations in the US. Its current recommendation reads: “We recommend screening mammography every two years for women aged 40 to 74.” Mammography is exactly what we commonly call a mammogram. This recommendation is rated as a Grade B. For women over 75, and for those with dense breast tissue who need additional ultrasound or MRI scans, the Task Force has concluded that there is not enough evidence to support such screening. - Evidence grade: A - Sources:US Preventive Services Task Force (2024). Breast Cancer: Screening. - Notes: The recommended starting age for screening varies by country. In China, some local guidelines and programs recommend starting at age 45. Women with a family history of breast cancer — such as parents, children or siblings who have had it — or those carrying BRCA mutations are at higher risk. They should consult a doctor individually to determine the right screening plan; the above recommendations do not apply to them. ### 18. For women over 30, HPV testing should be the first choice for cervical cancer screening - Cost: An HPV test costs between 100 and 300 yuan. Women with a negative result can get tested again only once every five years. The sampling process takes just a few minutes. - In plain terms: In that rural Indian trial, women who underwent just one HPV test in their lifetime had roughly half the risk of dying from cervical cancer and about 50% lower odds of being diagnosed with advanced-stage disease. At a cost of just 100–200 yuan per test, a negative result provides protection for five years. - Benefit: This trial in rural India used group-level rather than individual randomization, involving women aged 30–59. A single HPV test cut the risk of death from cervical cancer by roughly 48% (hazard ratio 0.52; 95% CI 0.33–0.83). It also reduced the likelihood of detecting late-stage disease by about 53% (HR 0.47; 95% CI 0.32–0.69). - Evidence grade: A - Sources:Sankaranarayanan R 等 (2009). HPV screening for cervical cancer in rural India. New England Journal of Medicine. - Notes: Even women who have received the HPV vaccine still need screening, since the vaccine does not protect against all viral types. What makes this study unique is that it was a randomized screening trial with mortality as the primary outcome and only one round of testing performed. ### 19. Starting colorectal cancer screening at ages 45–50: use fecal immunochemical tests or colonoscopies - Cost: Fecal tests cost just a few dozen yuan and can be done every 1–2 years. Colonoscopies cost several hundred to over a thousand yuan; those with negative results only need one every 10 years. Preparing for a colonoscopy requires setting aside a full day for bowel cleansing. - In plain terms: Getting a low-cost fecal occult blood test every year or two lowers the chance of dying from colorectal cancer by roughly 16%. For people who’ve had at least one round of screening, this risk drops by about 25%. In the group invited to undergo a colonoscopy, the likelihood of developing colorectal cancer over the next decade fell from 1.20% to 0.98%. - Benefit: Cochrane pooled data from multiple studies showing that individuals undergoing fecal occult blood screening have a roughly 16% lower risk of dying from colorectal cancer. The original RR was 0.84, with a 95% CI ranging from 0.78 to 0.90. For those who’ve had at least one screening round, this risk reduction reaches 25% (RR 0.75). The NordICC randomized trial likewise found that among participants invited to get a colonoscopy, colorectal cancer incidence dropped from 1.20% to 0.98% over 10 years; its RR was 0.82, with a 95% CI of 0.70–0.93. - Evidence grade: A - Sources:Hewitson P 等 (2007). Screening for colorectal cancer using the faecal occult blood test, Hemoccult. Cochrane Database of Systematic Reviews. ; Bretthauer M 等 (2022). Effect of Colonoscopy Screening on Risks of Colorectal Cancer and Related Death. New England Journal of Medicine. - Notes: This topic remains debated. The NordICC trial tracked participants based on whether they were invited to get a colonoscopy; the difference in colorectal cancer mortality between groups was 0.28% versus 0.31% (RR 0.90, 95% CI 0.64–1.16), a gap well within statistical margins of error. This suggests earlier estimates of colonoscopy’s mortality benefits may have been overstated, while evidence for fecal tests’ impact on mortality is more robust. Most national guidelines recommend starting screening at ages 45–50; those with a family history of colorectal cancer should begin even earlier. ### 20. People with cardiovascular disease and older adults should get a flu shot each year - Cost: One shot costs 50 to 150 yuan. It should be given once each autumn. - In plain terms: In a trial involving people after a heart attack, the yearly death rate dropped from 4.9% to 2.9% after they received the flu vaccine. For people with cardiovascular disease and older adults, getting one shot each autumn for just 50 to 150 yuan can make a real difference. - Benefit: This trial included 2,571 participants after a myocardial infarction; neither doctors nor patients knew who got the vaccine or the placebo. Over 12 months, the overall death rate was 2.9% in the vaccine group versus 4.9% in the placebo group. The hazard ratio was 0.59, with a 95% confidence interval of 0.39 to 0.89. Cardiovascular death rates also showed a hazard ratio of 0.59. Another study pooled multiple trials and found that flu vaccination lowered the rate of major cardiovascular events to 3.6% from 5.4% in the control group; the relative risk was 0.66, with a 95% confidence interval of 0.53 to 0.83. Cardiovascular death risk showed a relative risk of 0.74, though this fell within the margin of error and was not statistically significant (95% CI 0.42 to 1.30). - Evidence grade: A - Sources:Fröbert O 等 (2021). Influenza Vaccination After Myocardial Infarction: A Randomized, Double-Blind, Placebo-Controlled, Multicenter Trial. Circulation. ; Behrouzi B 等 (2022). Association of Influenza Vaccination With Cardiovascular Risk: A Meta-analysis. JAMA Network Open. ；Demicheli V 等 (2018). Vaccines for preventing influenza in the elderly. Cochrane Database of Systematic Reviews. （备注里说的那份 Cochrane 汇总） - Notes: This recommendation is somewhat controversial. The Grade A rating applies only to people with cardiovascular disease. For otherwise healthy older adults, a Cochrane review offers only limited evidence. Flu vaccination also lowered the seasonal flu infection rate from 6% to 2.4%. The review rated the evidence for infection outcomes as “low” quality and the evidence for mortality as “very low” quality. This review was published in 2018 by Demicheli V et al. ### 21. Getting the shingles vaccine after age 50 - Cost: The recombinant shingles vaccine requires two doses, costing roughly 3,000 to 4,000 yuan in total. This expense must be paid out of pocket. - In plain terms: In Phase 3 trials, this vaccine proved 97% effective at preventing shingles across all age groups. The downside is that both doses cost several thousand yuan, all paid by the patient. In exchange, there’s a 97% reduction in the likelihood of developing shingles. - Benefit: This Phase 3 trial involved 15,400 participants from 18 countries. Participants were randomly assigned to receive either the vaccine or a placebo, with follow-up lasting an average of 3.2 years. Over that time, 6 cases of shingles occurred in the vaccine group versus 210 in the placebo group. Expressed per 1,000 person-years, these figures translate to 0.3 versus 9.1 cases. One thousand person-years represents the number of cases observed in a group of 1,000 people over one year. The original report states, “The overall vaccine efficacy against shingles is 97.2% (95% CI 93.7–99.0, P<0.001).” Effectiveness ranged from 96.6% to 97.9% across all age brackets. - Evidence grade: A - Sources:Lal H, Cunningham AL, Godeaux O, et al. (2015). Efficacy of an adjuvanted herpes zoster subunit vaccine in older adults. New England Journal of Medicine, 372(22), 2087-2096. - Notes: This option ranks low in terms of cost-effectiveness primarily due to its high price. While shingles itself rarely proves fatal, its most troublesome complication is post-herpetic neuralgia, which can persist for months or even years. After vaccination, a notable percentage of recipients experience pain at the injection site and fever. In particular, severe side effects (graded as Grade 3) occurred in 17.0% of vaccine recipients versus 3.2% of those given a placebo. ### 22. Pneumococcal vaccine for people over 65 - Cost: Several hundred yuan. In some regions, it is provided free of charge for seniors. - In plain terms: In a trial involving 84,500 seniors, the 13-valent pneumococcal vaccine cut cases of pneumonia caused by strains it targets by roughly 46%, and reduced instances of the most severe invasive infections by 75%. However, it showed no effect on pneumonia cases caused by any other pathogens, so it won’t prevent all types of pneumonia. The absolute confidence interval width is 95.2%. - Benefit: Researchers in the Netherlands randomly assigned 84,500 seniors over 65 to two groups for comparison. They used the 13-valent pneumococcal conjugate vaccine. Its effectiveness against pneumonia caused by strains it targets was 45.6%, with a 95% confidence interval of 21.8–62.5. This figure refers to the specific bacterial strains the vaccine can protect against. For the most dangerous form of pneumococcal disease, the effectiveness was 75.0% (95% CI 41.4–90.8). No protective effect was observed against pneumonia cases caused by any other pathogens. - Evidence grade: A - Sources:Bonten MJ, Huijts SM, Bolkenbaas M, et al. (2015). Polysaccharide conjugate vaccine against pneumococcal pneumonia in adults. New England Journal of Medicine, 372(12), 1114-1125. - Notes: This vaccine only protects against the specific bacterial strains it targets; it does not prevent all types of pneumonia. The 23-valent polysaccharide vaccine commonly used for seniors in China is a different formulation from the 13-valent conjugate vaccine used in this trial, so the effectiveness figures here cannot be directly applied to that vaccine. ### 23. Testing for Helicobacter pylori and eradicating it if positive - Cost: The carbon-13 or carbon-14 breath test costs 100 to 200 yuan. Eradicating the bacteria requires taking four different medications for two weeks; the medication cost for that period is 200 to 500 yuan. The main difficulty is ensuring the full two-week course of medication is taken on schedule. - In plain terms: A 22-year follow-up study conducted in Linqu, Shandong, showed that individuals who had Helicobacter pylori eradicated had roughly half the risk of developing gastric cancer and about 40% lower risk of dying from it. Testing costs just 100–200 yuan, while eradication requires a two-week medication regimen. - Benefit: This randomized trial in Linqu, Shandong, followed participants for 22 years. Those who underwent Helicobacter pylori eradication therapy saw their risk of gastric cancer drop by nearly half. The original odds ratio was 0.48, with a 95% confidence interval ranging from 0.32 to 0.71. Their risk of dying from gastric cancer also fell by roughly 38% (hazard ratio 0.62; 95% CI 0.39–0.99). - Evidence grade: A - Sources:Li WQ 等 (2019). Effects of Helicobacter pylori treatment and vitamin and garlic supplementation on gastric cancer incidence and mortality: follow-up of a randomized intervention trial. BMJ. - Notes: Reinfection can still occur after eradication, so it is advisable for all household members to be tested and treated together. This trial involved residents of an area with a high incidence of gastric cancer; people living in regions with lower incidence may gain considerably less benefit. ### 24. Heavy smokers should get a low-dose chest CT once a year - Cost: The test costs 200–400 yuan per session and takes just 10 minutes. You must also factor in follow-up tests after any false alarms, plus the anxiety that comes with waiting for results. - In plain terms: Eligible heavy smokers who get a low-dose CT once a year have a 20% lower risk of dying from lung cancer and a 6.7% lower overall risk of death compared to those who only get regular chest X-rays. The trade-offs are extra follow-up tests after any suspicious findings and the resulting worry during the waiting period. - Benefit: The NLST trial in the U.S. enrolled 53,454 participants aged 55–74 with at least 30 pack-years of smoking history and who had quit smoking no more than 15 years prior. Those who underwent low-dose CT had a 20.0% relative reduction in lung cancer deaths versus those who only got chest X-rays. The 95% confidence interval is 6.8–26.7. Overall mortality dropped by 6.7% relative to controls, with a 95% CI of 1.2–13.6. - Evidence grade: A - Sources:National Lung Screening Trial Research Team (2011). Reduced Lung-Cancer Mortality with Low-Dose Computed Tomographic Screening. New England Journal of Medicine. - Notes: This recommendation applies only to high-risk smokers. In the same study, 24.2% of CT recipients showed suspicious findings, yet 96.4% of those cases turned out to be false positives. For non-smokers, undergoing this test offers no benefit and only adds unnecessary anxiety. ### 25. Call 12356 if you’re depressed or having suicidal thoughts; don’t keep sleeping pills or pesticides at home - Cost: There’s no cost involved. You just need to make one phone call. Plus, lock away any medications and keep pesticides out of the house. - In plain terms: Removing lethal items from easy reach is a proven way to cut suicide risk: after restricting access to painkillers, suicide rates linked to them dropped by 43%; installing barriers at locations where people often jump off cliffs cut rates by 86%. That’s why it’s a good idea to avoid storing sleeping pills and pesticides at home. If you’re feeling overwhelmed, call 12356 — this national helpline is available at least 18 hours a day. - Benefit: A recent review of nearly a decade’s worth of research confirms that limiting people’s access to lethal means is an effective suicide prevention strategy. After controls on painkiller availability were put in place, suicide cases tied to these drugs fell by 43%. Installing protective barriers at common suicide hotspots reduced rates by 86% (the 95% confidence interval ranges from 79% to 91%). School-based cognitive intervention programs also lowered rates of attempted suicide by roughly 55% (OR 0.45, 95% CI 0.24–0.85). Antidepressant medications and psychotherapy are also key components of suicide prevention. Starting May 1, 2025, the 12356 helpline will be available nationwide in China, operating at least 18 hours each day. - Evidence grade: B - Sources:Zalsman G 等 (2016). Suicide prevention strategies revisited: 10-year systematic review. Lancet Psychiatry. ; 国家卫生健康委 (2024). 关于应用"12356"全国统一心理援助热线电话号码的通知（国卫医政函〔2024〕259 号）. - Notes: The B rating is based on two factors: most evidence supporting restrictive measures comes from ecological studies that compare suicide rates before and after policy implementation; there is currently no direct evidence that the helpline itself reduces overall mortality rates. Suicidal impulses typically last only a few minutes to a few hours, so simply removing lethal items from immediate reach is a meaningful intervention on its own. Data on outcomes over longer time periods following suicide attempts, as well as information on long-term consequences for survivors, can be found in Item 32 of this section (“Tell someone close to you as soon as suicidal thoughts arise”). ### 26. Purchase fire extinguishers, fire blankets, escape respirators, and first-aid kits, then inspect them once a year - Cost: A set of fire extinguishers, fire blankets, one respirator per person, and a first-aid kit costs a few hundred yuan. You only need to buy it once; after that, it takes just 10 minutes each year to inspect the items. - In plain terms: Fire extinguishers, fire blankets, escape respirators, and first-aid kits are all included in the Emergency Management Department’s list of 11 essential items for household emergency preparedness. The whole set costs a few hundred yuan, and you only need to buy it once. Studies of home safety programs that included on-site guidance found these measures cut injury rates by roughly 25%. - Benefit: The Emergency Management Department’s “National Recommended List of Basic Household Emergency Supplies” contains 11 items in total. Among them, “fire extinguishers and fire blankets” are recommended for “putting out small fires at the initial stage”, and the list also notes that “fire blankets can be draped over the body to aid escape”. The “escape respirators” listed are “firefighting filtering self-rescue respirators designed for use during fire escapes”. “External medical supplies” refer to “hemostatic powder, adhesive bandages, gauze bandages, and other items used to treat wounds”. Cochrane analyzed 98 studies involving 2,605,044 participants in total. Home safety interventions lowered injury rates to an IRR of 0.89; the 95% confidence interval for this figure is 0.78 to 1.01. For interventions that included on-site guidance, injury rates dropped by around 25% (IRR 0.75, 95% CI 0.62 to 0.91). - Evidence grade: B - Sources:应急管理部 (2020). 全国基础版家庭应急物资储备建议清单. ; Kendrick D 等 (2012). Home safety education and provision of safety equipment for injury prevention. Cochrane Database of Systematic Reviews. ; 武胜县市场监督管理局 (2025). 手提式灭火器、防火门（窗）、点型感温（烟）火灾探测器消费提示. - Notes: This finding is somewhat controversial. The same Cochrane meta-analysis found that interventions that did not provide emergency supplies also lowered injury rates by roughly 20%. The original IRR for those interventions was 0.78, with a 95% confidence interval of 0.66 to 0.92. Providing emergency supplies alone did not yield better results than other measures. The main effect of these interventions comes from on-site education and home modifications, so the benefit of supplying emergency supplies is rated as “moderate” rather than “significant”. When buying fire extinguishers, look for the CCC certification mark; for pre-pressurized extinguishers, make sure the pressure gauge needle points to the green zone. Details on smoke alarms and carbon monoxide detectors are covered in section 3 of this chapter. Instructions for using tourniquets can be found in section 13, item 12. Guidance on how to select, store, and replace each item can be found in [docs/家庭应急装备清单.md](../../docs/research/家庭应急装备清单.md). ### 27. Visible blood in urine — even if painless and gone by the next day — still warrants a check-up - Cost: A routine urine test costs just a few dozen yuan, while a urinary-system ultrasound runs around 100–200 yuan. If a doctor deems it necessary, a cystoscopy can be added at a cost of roughly 1,000 yuan. - In plain terms: Among people aged 60 and older, the chance of ultimately being diagnosed with bladder cancer after experiencing one episode of visible blood in urine is about 2.8%. For those aged 40–59, that figure is roughly 1.2%. These percentages may not seem very high, but they’re high enough to justify getting checked — even if the bleeding stops the very next day. - Benefit: A UK study analyzed electronic medical records from primary-care clinics, comparing 4,915 patients diagnosed with bladder cancer against 21,718 controls. Among patients with visible blood in urine, the proportion ultimately found to have bladder cancer was 2.8% for those aged 60+, with a 95% confidence interval of 2.5–3.1. For ages 40–59, the figure was 1.2%, with a 95% CI of 0.6–2.3. This proportion is known as the positive predictive value. Blood visible only under a microscope also carries significance; the odds ratio is 20, with a 95% CI of 12–33. For those over 60, this figure is 1.6%, with a 95% CI of 1.2–2.1. - Evidence grade: B - Sources:Price SJ, Shephard EA, Stapley SA, Barraclough K, Hamilton WT (2014). Non-visible versus visible haematuria and bladder cancer risk: a study of electronic records in primary care. British Journal of General Practice, 64(626), e584-e589. - Notes: The absence of pain is a key clue. Blood in urine caused by kidney stones or infections usually comes with abdominal or flank pain, plus frequent, urgent, or painful urination. Cancer-related bleeding, however, often causes no discomfort at all and may disappear for a few days before returning — which is why many people overlook it. Taking anticoagulant medications is not a valid reason to skip testing. Blood in urine after intense exercise or during a woman’s menstrual period can be re-evaluated before deciding on further checks. The benefit is rated “low” because it reflects only detection rates, not any measurable reduction in mortality resulting from early diagnosis. ### 28. If erectile dysfunction appears, check cardiovascular health first — don’t treat it as a purely sexual issue - Cost: A doctor’s visit costs just a few dozen yuan. Measuring blood pressure and running tests for blood sugar and cholesterol adds another hundred or so yuan. One trip to the hospital yields results after a few days. - In plain terms: Men with erectile dysfunction later develop cardiovascular disease at roughly 40% higher rates than other men, and heart attacks at about 60% higher rates. The younger a man is, the greater this difference becomes. This problem often shows up before any chest pain does. Therefore, it’s wise to check blood pressure, blood sugar, and cholesterol levels rather than simply self‑medicating. - Benefit: One meta‑analysis combined data from 14 long‑term studies involving 92,757 men, followed for an average of 6.1 years. Compared with men without erectile dysfunction, those with the condition faced higher risks as follows: overall cardiovascular events rose by roughly 44% (RR 1.44, 95% CI 1.27–1.63). Heart attacks increased by about 62% (RR 1.62, 95% CI 1.34–1.96). Cerebrovascular events rose by roughly 39% (RR 1.39, 95% CI 1.23–1.57). All‑cause mortality went up by about 25% (RR 1.25, 95% CI 1.12–1.39). No significant difference appeared for cardiovascular‑related deaths (RR 1.19, 95% CI 0.97–1.46). The risk elevation was greater in younger men and in those whose baseline cardiovascular risk was moderate. Studies that used questionnaire‑based diagnosis reported an RR of 1.61 (95% CI 1.38–1.86), while studies asking just one question gave an RR of 1.27 (95% CI 1.18–1.37). - Evidence grade: A - Sources:Vlachopoulos CV, Terentes-Printzios DG, Ioakeimidis NK, Aznaouridis KA, Stefanadis CI (2013). Prediction of cardiovascular events and all-cause mortality with erectile dysfunction: a systematic review and meta-analysis of cohort studies. Circulation: Cardiovascular Quality and Outcomes, 6(1), 99-109. ；DailyMed（美国国立医学图书馆的药品说明书库）. VIAGRA (sildenafil citrate) tablet, CONTRAINDICATIONS. - Notes: These 14 studies tracked groups of men over time; they are not randomized controlled trials. Hence the “40% higher” figure reflects an association, not a proven cause‑and‑effect relationship. Occasional episodes do not count; the condition is considered present only when symptoms persist for three months or more. The tests recommended — blood pressure measurement, fasting blood‑glucose testing, plus cholesterol checks, smoking status assessment, and waist‑circumference measurement — are the same as those listed in sections 7 and 8 of this chapter. Avoid purchasing “male‑enhancement” supplements online; legitimate medications for this purpose are prescription drugs, and their instructions list nitrates as a contraindication — meaning men already taking nitroglycerin or similar drugs must not use them, as doing so can cause a sudden drop in blood pressure. For ways to improve erectile function, see section 29 (weight loss and smoking cessation can help). The benefit is rated “moderate” rather than “large”: the 44% figure represents the difference between two groups, not the actual reduction in mortality achieved by testing. It is also not “small”; unlike the situation described in section 27 (visible blood in urine), where detection alone is the benefit, here hypertension, diabetes, and abnormal cholesterol levels each have established treatments available. ### 29. Weight loss, quitting smoking, and controlling blood pressure and blood sugar can improve erectile function - Cost: There is no cost involved; in fact, it may even save money. The real challenge is staying consistent over time — eating healthily, exercising regularly, and quitting smoking. - In plain terms: Managing cardiovascular risk factors naturally leads to better erectile function. When multiple randomized trials are combined, questionnaire scores improve by an average of 2 to 3 points. This questionnaire has a maximum score of 25, with scores above 22 considered normal. - Benefit: One meta-analysis evaluated six randomized controlled trials involving 740 men. Interventions included lifestyle changes or medication to control cardiovascular risk factors, with follow-ups lasting at least six weeks. Overall, erectile function scores on the IIEF-5 questionnaire rose by an average of 2.66 points (95% CI: 1.86–3.47). When two trials using statins (143 participants) were excluded, the remaining four trials relying solely on lifestyle changes still showed an average improvement of 2.40 points (95% CI: 1.19–3.61). A total of 597 men participated in these four trials. The IIEF-5 consists of five questions scored from 5 to 25; scores between 22 and 25 indicate no erectile dysfunction, while scores of 5–7 indicate severe impairment. - Evidence grade: A - Sources:Gupta BP, Murad MH, Clifton MM, Prokop L, Nehra A, Kopecky SL (2011). The effect of lifestyle modification and cardiovascular risk factor reduction on erectile dysfunction: a systematic review and meta-analysis. Archives of Internal Medicine, 171(20), 1797-1803. ；Rosen RC, Cappelleri JC, Smith MD, Lipsky J, Peña BM (1999). Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5) as a diagnostic tool for erectile dysfunction. International Journal of Impotence Research, 11(6), 319-326. - Notes: These six trials used different interventions — some combined weight loss and exercise, while others used medication to control blood pressure and lipids. With only 740 participants overall, the results confirm a positive trend, though the exact degree of improvement varies per individual. The benefit is rated as “minor” because the outcome measured was solely questionnaire scores, not actual reductions in disease incidence. However, similar lifestyle changes have been shown to produce measurable health benefits elsewhere: quitting smoking (see Section 2, Item 1), maintaining a BMI between 20–25 through weight control (Section 2, Item 33), and managing blood pressure with medication when necessary (Section 7). Prescription medications are acceptable when prescribed by a doctor; caution is advised with over-the-counter “health supplements,” which may contain unregulated amounts of active ingredients. For guidance on identifying safe products, see Section 28, Item 4. ### 30. Always use condoms during sex and never share needles - Cost: A single condom costs just one or two yuan. The challenge isn’t the price, but making sure to use one every single time — and putting it on right from the start. - In plain terms: Using a condom every time throughout sex cuts the chance of HIV transmission between heterosexual partners by roughly 70% or more. “Most of the time” just isn’t enough — that still leaves the risk nearly as high as not using one at all. Condoms also protect against syphilis, gonorrhea, and other STIs. - Benefit: One study pooled data from 25 separate studies involving 10,676 heterosexual couples in which one partner was HIV‑positive and the other was not. Compared to couples who never used condoms, those who consistently used them saw their HIV transmission risk drop by about 71%. The reported relative risk was 0.29, with a 95% confidence interval of 0.20–0.43. When compared to couples who used condoms only intermittently, the risk was lower by roughly 77% (RR = 0.23; 95% CI 0.13–0.40). The authors concluded that although condoms are not perfect, “consistent use can reduce HIV transmission by more than 70%.” This same level of protection also applies to syphilis, gonorrhea, chlamydia, and other sexually transmitted infections. - Evidence grade: A - Sources:Giannou FK, Tsiara CG, Nikolopoulos GK, et al. (2016). Condom effectiveness in reducing heterosexual HIV transmission: a systematic review and meta-analysis of studies on HIV serodiscordant couples. Expert Review of Pharmacoeconomics & Outcomes Research, 16(4), 489-499. ；Fonner VA 等 (2016). Effectiveness and safety of oral HIV preexposure prophylaxis for all populations. AIDS. （暴露前预防 PrEP） - Notes: The difference between “infrequent use” and “no use” is minimal; the whole benefit hinges on the phrase “every time, throughout.” Sharing needles is a separate, highly effective route of transmission that has nothing to do with sex — this includes drug injection, tattooing, and piercing. For people at high risk, pre‑exposure prophylaxis (PrEP) offers another option: taking medication in advance to block infection. Pooled data from 18 studies show that when at least 70% of participants adhered to the regimen, PrEP cut HIV risk by about 70% compared to placebo (RR = 0.30; 95% CI 0.21–0.45). Trials with lower adherence rates showed no protective effect. PrEP is a prescription medication; consult an infectious‑disease specialist or public‑health clinic rather than ordering it online. Information on what to do after potential exposure can be found in Section 13. ### 31. If you’ve engaged in high‑risk behavior, get tested for HIV — the Chinese CDC offers free testing with full confidentiality - Cost: There is no charge. You simply visit the Chinese CDC or a designated medical facility and provide a blood sample. The only real hurdle is mustering the courage to get tested at all. - In plain terms: Testing for HIV at the Chinese CDC costs nothing. According to the “National Measures for HIV Testing Management,” staff are prohibited from disclosing your name, address, or test results. A positive result does not mean a death sentence: people who adhere to treatment and keep their viral load undetectable cannot transmit the virus to sexual partners. One major study followed more than 700 couples through over 70,000 unprotected acts; there were zero transmissions between partners. - Benefit: Article 23 of the “Regulations on HIV/AIDS Prevention and Control” mandates that local health authorities designate medical institutions to provide free counseling and initial screening to anyone who voluntarily seeks testing. Early detection is far more than a psychological comfort — modern antiretroviral therapy can drive the virus down to undetectable levels. The World Health Organization states that individuals on such treatment with an undetectable viral load pose no risk of HIV transmission. The PARTNER study observed 782 same‑sex couples (serodiscordant pairs) for a total of 1,593 person‑years; despite 76,088 unprotected encounters, only 15 new infections occurred, and genetic analysis proved none originated from the partner. The same national measures also forbid any disclosure of patients’ personal data or test outcomes. - Evidence grade: A - Sources:国务院 (2006). 艾滋病防治条例（第三、二十三、三十八、三十九条）. （北京市卫生健康委员会转载）；Rodger AJ, Cambiano V, Bruun T, et al. (2019). Risk of HIV transmission through condomless sex in serodifferent gay couples with the HIV-positive partner taking suppressive antiretroviral therapy (PARTNER): final results of a multicentre, prospective, observational study. The Lancet, 393(10189), 2428-2438. ；广东省疾病预防控制中心. 艾滋病检测窗口期科普. （窗口期那个数字；原页面已下线，链接为 2026-09-15 的网页存档） - Notes: The “window period” determines when a test becomes reliable. The Guangdong Provincial CDC reports that nucleic‑acid tests can detect HIV after roughly one week, fourth‑generation antigen‑antibody tests after about two weeks, and third‑generation antibody tests after three weeks. It is advisable to wait at least two weeks post‑exposure and then retest after another two to four weeks; after three months, 99.99% of people can be certain they are not infected. A positive home‑test result is not a diagnosis — confirmation must come from the Chinese CDC or a certified lab. Article 3 of the regulations guarantees that no one may discriminate against HIV‑positive individuals or their families; their rights to marriage, employment, medical care, and education are protected by law. Article 38 also requires infected persons to inform any sexual partners of their status. Screening for HIV, syphilis, and hepatitis B during pregnancy and related prevention measures are covered in Section 27. ### 32. As soon as suicidal thoughts arise, tell someone nearby and hand over those first few minutes - Cost: No cost involved. The hard part is actually speaking up at that moment and admitting you can’t be alone for a few hours. - In plain terms: Among 82 people who attempted suicide, 47.6% reported that only 10 minutes or less passed from the first appearance of suicidal thoughts to the actual attempt. What they had to endure was not a lifetime of mental anguish, but just those few minutes. Of the same group, 76.8% had some contact with others during that time, though they did not voice their feelings. Looking ahead, about 2% of people who ended up in the hospital due to self-harm died by suicide within a year, while roughly 7% did so after nine years or more; the vast majority did not follow that path. - Benefit: Interviews conducted within three days of admission with those 82 individuals showed that 47.6% (39 people) stated the interval between the first emergence of suicidal thoughts and the actual attempt was no more than 10 minutes. Those whose process took longer displayed significantly higher scores on measures of suicidal intent. However, impulse scores showed no correlation with the duration of this period. Additionally, 76.8% (63 people) reported having some sort of interaction with a partner, family member, or friend during those minutes. The authors conclude that the window for intervention is usually very brief, leaving limited room for professionals to step in; thus, it is crucial to spread awareness of warning signs and basic intervention methods to ordinary people. Another systematic review compiled findings from 90 follow-up studies. For those seeking medical care after self-harm, the median rate of repeated self-harm without resulting in death was 16% after one year, while the suicide mortality rate at that point stood at 2%. After nine years or more of follow-up, roughly 7% had died by suicide. - Evidence grade: B - Sources:Deisenhammer EA, Ing CM, Strauss R, Kemmler G, Hinterhuber H, Weiss EM (2009). The duration of the suicidal process: how much time is left for intervention between consideration and accomplishment of a suicide attempt? Journal of Clinical Psychiatry, 70(1), 19-24. ；Owens D, Horrocks J, House A (2002). Fatal and non-fatal repetition of self-harm: systematic review. British Journal of Psychiatry, 181, 193-199. - Notes: Grade B is assigned for two main reasons: the Deisenhammer study involved only 82 participants from a single hospital and relied on retrospective recollections; Owens’s review aggregated median figures from 90 studies employing different methods, rather than producing a single combined statistic. That same review also emphasizes that the suicide risk among self-harm patients remains hundreds of times higher than in the general population. Consequently, the statement “the vast majority did not follow that path” describes the overall trajectory of this group, not a guarantee for any individual; appropriate medical care must still be sought. For advice on removing lethal means and contacting the helpline 12356, see item 25 in this section. Steps to take when feeling down are outlined in item 19 of Section 3. Long-term consequences following survival are discussed in item 33 of this section. Finally, actions you can take if someone close to you expresses such thoughts are detailed in item 15 of Section 8. ### 33. Don’t treat “survival” as a safety net: after ingesting paraquat or inhaling carbon monoxide, emergency care can save lives, but it rarely preserves lung or brain function - Cost: No cost involved. It simply helps you understand this reality up front. - In plain terms: There is no antidote for paraquat. Gastric lavage is not recommended, and neither hemofiltration nor dialysis alters its disease progression. Paraquat actively enters lung tissue against its concentration gradient, causing pneumonia and pulmonary fibrosis, while also damaging kidneys and liver. Among 257 cases treated at ten hospitals in Bangladesh, the mortality rate reached 43.2%. Carbon monoxide produces similar outcomes: six weeks after exposure, 46.1% of patients receiving normal oxygen still suffered cognitive impairment, compared to 25.0% of those receiving hyperbaric oxygen therapy. No treatment pathway yields a completely clean outcome; the most common result is lasting health complications. - Benefit: A systematic review on paraquat poisoning highlights its extremely high mortality rate, stemming from its intrinsic toxicity and lack of effective treatments. Paraquat is actively transported into lung tissue against its concentration gradient, resulting in pneumonia, pulmonary fibrosis, kidney and liver damage. The review explicitly advises against gastric lavage; hemofiltration and dialysis are unlikely to alter clinical outcomes. Evidence supporting corticosteroids or immunosuppressants remains weak. It also notes that mortality rates remain high across all centers despite varying treatment approaches. In Bangladesh, 257 out of 1,420 cases admitted to ten tertiary hospitals between 2013 and 2024 resulted in death (43.2%). Common symptoms included lower limb swelling due to acute kidney failure (71.2%), vomiting (65.8%) and abdominal pain (58.0%). Another randomized, double-blind trial involving 76 patients per group examined acute carbon monoxide poisoning; six weeks later, 25.0% of those receiving hyperbaric oxygen therapy and 46.1% of those receiving normal oxygen still had cognitive impairments (P=0.007; adjusted OR 0.45, 95% CI 0.22–0.92). A separate study of 73 patients found 30% developed cognitive impairments and 12% showed hyperintense signals in white matter on brain imaging. Since July 1, 2014, China has banned the registration and production of paraquat aqueous solutions; sales and usage ceased by July 1, 2016. As of September 26, 2020, soluble concentrate formulations are also prohibited nationwide. Official documents cite frequent suicide attempts involving paraquat as the primary reason for these strict controls. - Evidence grade: B - Sources:Gawarammana IB, Buckley NA (2011). Medical management of paraquat ingestion. British Journal of Clinical Pharmacology, 72(5), 745-757. ；Chowdhury FR 等 (2026). Clinical and Laboratory Profile of Paraquat Poisoning: A Toxicological Crisis in Bangladesh. American Journal of Tropical Medicine and Hygiene, 115, 176-182. ；Weaver LK, Hopkins RO, Chan KJ, et al. (2002). Hyperbaric oxygen for acute carbon monoxide poisoning. New England Journal of Medicine, 347(14), 1057-1067. ；Parkinson RB, Hopkins RO, Cleavinger HB, et al. (2002). White matter hyperintensities and neuropsychological outcome following carbon monoxide poisoning. Neurology, 58(10), 1525-1532. ；农业农村部办公厅 (2018). 关于切实加强百草枯监督管理的通知（农办农〔2018〕17 号）. - Notes: Grade B is assigned because these studies involve general poisoning patients rather than solely suicide attempt survivors; the carbon monoxide trial even included accidental poisoning cases. Consequently, observed complication rates cannot be directly interpreted as probabilities specific to suicide attempts. This entry does not compare mortality rates across different treatment methods nor recommend any specific actions. The sole certainty is that no treatment pathway guarantees a completely clean outcome. On-site management of carbon monoxide poisoning is detailed in Section 13, Item 19. For accidental ingestion of pesticides or medications, avoid inducing vomiting and seek medical help while bringing the container along (Section 13, Item 20). Finally, refrain from storing pesticides or sedatives at home (Section 13, Item 25). ### 34. Don’t bet on “a few days of rest” after a fall from height: most patients admitted to a trauma ICU survive, though at a cost measured in years - Cost: No cost at all. It simply helps you see the full picture. - In plain terms: A trauma ICU in southern Xinjiang treated 289 patients who fell from heights. Only 5.5% died either in the hospital or within 30 days. The vast majority survived, but at a price: 47.1% suffered injuries to three or more body parts, 36% needed ventilators, and the median length of stay in the ICU was 8 days — with some patients remaining for as long as 132 days. The median fall height for this group was just 3 meters. Follow‑up showed that 58% of those with serious injuries eventually returned to work. - Benefit: From April 2020 to July 2024, the same ICU recorded 289 cases of falls from heights; the average age of patients was 40.3 years. The median fall height was 3 meters; 26.6% fell from heights above 5 meters and 11.4% from heights above 10 meters. The median Injury Severity Score was 24, a higher score indicating more severe injuries; 63.3% of patients scored above 20. In addition to the multiple injuries, 18.3% suffered damage to four or more body parts. Mechanical ventilation was required for 36% of patients, with a median duration of 103.5 hours. The median ICU stay was 8 days, ranging from 1 day to 132 days. The in‑hospital or 30‑day mortality rate was 5.5% (16 out of 289). A German trauma center reported similar results: among 84 patients with an ISS of 25 or higher, 58% returned to work after follow‑up. Age, length of ICU treatment, and self‑reported health status were identified as predictive factors. Nationwide, the average cost per hospital stay in 2024 was 9,870 yuan, a 4.3% decrease from the previous year; total health expenditures reached 9,089.55 billion yuan, of which personal spending accounted for 2,500.75 billion yuan, or 27.5% of the total. - Evidence grade: B - Sources:Chen Y, Li W, Wang X, Zhong Q, Abudurexiti A, Qiu Q, Li J, Luo J (2025). Clinical features and prognostic predictors for patients admitted to trauma intensive care unit due to fall from height in South Xinjiang. International Journal of Emergency Medicine, 18, 142. ；Simmel S, Wurm S, Drisch S, Woltmann A, Coenen M (2020). Prädiktion der Rückkehr zur Arbeit nach Polytrauma bei Patienten mit einem ISS von mindestens 25. Die Rehabilitation, 59(2), 95-103. ；国家卫生健康委 (2025). 2024 年我国卫生健康事业发展统计公报解读. - Notes: Grade B is assigned because the fall‑related data come from a single hospital’s retrospective chart review without distinguishing between accidental and self‑inflicted falls. The figure on return‑to‑work is based on only 84 patients in Germany; neither dataset can be taken as a reliable predictor of outcomes for any individual who falls from a height. The average national hospital cost is an overall figure, not specific to fall injuries; it is included only to provide a baseline for comparison. No direct correlation between fall height and injury severity is presented, as the source only supplies the height distribution of this group. For information on pressure ulcers that often develop during prolonged bed rest, see Section 17, Item 8. Deep‑vein thrombosis and pulmonary embolism are discussed in Section 13, Item 11 (sudden swelling of one leg). If suicidal thoughts arise, refer to Section 32 of this chapter. Details on paraquat poisoning are covered in Section 33 — remember that “being saved” does not guarantee a completely uncomplicated recovery. The timeline described here reflects the author’s own experience: after falling from the fourth floor, he initially believed he would recover in a few weeks, but ended up hospitalized for a full year, undergoing multiple surgeries, wearing steel plates, and unable to sit up on his own for half a year; his family had to take on debt to cover the expenses. ### 35. Don’t trade “losing one kidney is no big deal” for cash: the remaining kidney has to do the work of two, and 86% of kidney sellers later say their health got worse - Cost: No cost at all. It simply requires a clear look at the facts. - In plain terms: First, consider the best-case scenario: legitimate donors who pass rigorous screening and receive post‑surgery follow‑up. In U.S. data from nearly 96,000 donors, only 31 per 10,000 developed end‑stage renal disease within 15 years after donation. Among equally healthy, eligible non‑donors, that figure was just 4 per 10,000. On the other side, a study of 305 kidney sellers in India found that six years later, 86% reported poorer health, and three‑quarters still carried debt. Legitimate donors get screening and monitoring; kidney sellers get none of that. - Benefit: U.S. researchers compared 96,217 living kidney donors with 20,024 similarly healthy non‑donors drawn from the NHANES III survey. After 15 years, the estimated risk of developing end‑stage renal disease (ESRD) was 30.8 per 10,000 donors (95% CI 24.3–38.5) versus 3.9 per 10,000 non‑donors (95% CI 0.8–8.9; P<0.001). Over a lifetime, ESRD risk was 90 per 10,000 donors, 14 per 10,000 non‑donors, and 326 per 10,000 in the general population. A Norwegian study of 1,901 donors (median follow‑up 15.1 years) showed a 30% higher overall mortality (HR 1.30, 95% CI 1.11–1.52), a 40% higher cardiovascular mortality (HR 1.40, 95% CI 1.03–1.91), and roughly tenfold higher ESRD risk (HR 11.38, 95% CI 4.37–29.6). Among 3,698 U.S. donors, 11 developed ESRD — an incidence of 180 per million person‑years, compared with 268 per million in the general population. Of those re‑examined after an average of 12.2 years, 255 remained healthy, and 85.5% retained a glomerular filtration rate of at least 60 ml/min/1.73 m², the clinical lower limit of normal. Hypertension affected 32.1% and proteinuria 12.7%. In Chennai, India, 96% of 305 kidney sellers acted to pay debts; they received an average of $1,070. Six years post‑surgery, family income fell by one‑third (P<0.001), poverty rose, and three‑quarters remained indebted; 86% said health worsened, and 79% would not recommend kidney selling to others. The absolute numbers from these studies are 32,621 donors, 24.9 years of follow‑up, 302 ESRD cases, and 9.2 years of average follow‑up after surgery. - Evidence grade: A - Sources:Muzaale AD, Massie AB, Wang MC, Montgomery RA, McBride MA, Wainright JL, Segev DL (2014). Risk of end-stage renal disease following live kidney donation. JAMA, 311(6), 579-586. ；Mjøen G, Hallan S, Hartmann A, et al. (2014). Long-term risks for kidney donors. Kidney International, 86(1), 162-167. ；Ibrahim HN, Foley R, Tan L, et al. (2009). Long-term consequences of kidney donation. New England Journal of Medicine, 360(5), 459-469. ；Goyal M, Mehta RL, Schneiderman LJ, Sehgal AR (2002). Economic and health consequences of selling a kidney in India. JAMA, 288(13), 1589-1593. - Notes: Controversy exists: Ibrahim’s study used ordinary citizens as controls and found no difference in survival or ESRD risk between donors and non‑donors. Muzaale and Mjøen compared donors to equally healthy, eligible non‑donors and found markedly higher risks. The disagreement concerns the control group, not the donors themselves. All three studies agree that absolute risks remain low (30.8 per 10,000 over 15 years). Thus the key points are two: first, the remaining kidney does bear extra strain, as shown by higher rates of hypertension and proteinuria; second, these figures apply only to donors who undergo pre‑ and post‑operative screening and medical care — conditions absent for illegal kidney sellers, whose outcomes differ sharply according to Indian follow‑up data. Original studies provide only self‑reported health decline, proteinuria, hypertension, and ESRD rates; no figures on bed‑bound status are included here. Legal restrictions on organ sales, fines, and criminal penalties for relatives are detailed in Section 9, Article 22. Dialysis patients may use cross‑regional settlement and long‑term medication programs described in Section 16, Articles 1 and 2. ### 36. Don’t pick up, disassemble, or sell unidentified metal parts; stay clear of areas marked with the clover symbol - Cost: No cost involved. If you see unfamiliar metal cylinders, lead containers, or parts removed from equipment, simply steer clear — don’t pick them up, take them apart, or put them in your pocket. - In plain terms: Radiation has no smell, color, or temperature. Most radioactive sources look like ordinary pieces of metal, so “it looks harmless” is not a reliable indicator. The chance of an ordinary person encountering one is extremely low — fewer than one incident occurs per 10,000 sources each year. Yet when such an encounter does happen, the consequences are irreversible. In 1987, four people died in Brazil after dismantling a radiotherapy machine from an abandoned clinic. - Benefit: As of 2025, roughly 178,000 radioactive sources and 355,000 radiation devices are in use nationwide. The annual rate of radiation incidents involving sources remains below one per 10,000 sources. Classification is as follows: loss, theft, or uncontrolled release of Category I or II sources constitutes a major radiation incident; Category III is a relatively serious incident. Loss or theft of Category IV or V sources, or exposure exceeding annual dose limits, counts as a minor incident. Official example: In June 2020, a γ‑ray inspection was performed during pipeline upgrades at a steel plant in Ningxia. A Category II iridium‑192 source exposed three workers to radiation; one suffered third‑degree acute skin damage, another had fourth‑degree injuries on several fingers, and a third had first‑ to second‑degree burns. All three received doses far above legal limits; both responsible firms had their radiation licenses revoked and were fined 70,000 yuan. International example: In 1987, 50.8 TBq of cesium‑137 was removed from a radiotherapy machine in Goiânia, Brazil, after the device was dismantled; the source’s protective casing was ruptured. About 112,000 people were screened; 249 showed internal or external contamination, 129 of whom required moderate to severe medical care. Four people ultimately died. (National and international statistics) - Evidence grade: A - Sources:生态环境部 (2025). 2024 中国生态环境状况公报. ；国家核安全局 (2026). 2025 年我国核与辐射安全监管工作成效. ；生态环境部 (2021). 关于一起 γ 射线探伤作业违法违规造成辐射事故案件处理情况的通报. ；国务院 (2019). 放射性同位素与射线装置安全和防护条例（2019 年修订，第三十四、四十二、六十八条）. ；环境保护部 (2009). 关于建立放射性同位素与射线装置辐射事故分级处理和报告制度的通知（辐射事故分级标准）. ；International Atomic Energy Agency (1988). The Radiological Accident in Goiânia. IAEA, Vienna. - Notes: If you ever encounter such a source, move away, note its location, do not touch it, and call 110. Reporting is mandatory to environmental, police, and health authorities. Distance and time are the only effective safeguards; plastic bags or pockets offer no protection. Devices such as X‑ray machines or CT scanners emit radiation only when powered; once turned off, they pose no residual risk. The real danger lies in the sealed radioactive source inside them. Radiotherapy machines, pipeline and boiler inspection devices, well‑logging tools, and level gauges all contain such sources, which look identical to ordinary metal parts. Therefore, never try to identify a source — simply avoid picking up, selling, or taking home any unidentified equipment parts. Workers in scrap recycling, dismantling, hardware, and construction face higher risks; they should steer clear of any area marked with the clover warning symbol. Nuclear plant leaks represent a different type of incident, with an even lower probability of affecting the general public. The primary beneficiaries of these precautions are you and anyone else present at the scene. ### 37. When gambling leads to borrowing money and persistent low mood, call 12356 first and then hand over your bank cards and payment passwords to family members - Cost: No cost involved. Simply make one phone call and give your bank cards, payment passwords, and gambling apps to a family member. The hardest part is admitting that you’ve lost control over your gambling behavior. - In plain terms: Individuals who have sought treatment for gambling problems are 15 times more likely to die by suicide and 1.8 times more likely to die overall compared to their peers. Depression serves as a key warning sign for potential suicide. Therefore, if you find yourself gambling despite owing money and feeling persistently down, call 12356 right away. - Benefit: A nationwide Swedish registry study examined 2,099 individuals diagnosed with gambling disorder between 2005 and 2016. Gambling disorder is defined as an inability to control gambling habits, which negatively impacts daily life. Compared to the general Swedish population aged 20–74, these individuals showed a 1.8-fold increase in overall mortality and a 15-fold increase in suicide mortality (these figures represent standardized mortality ratios). Over the follow-up period, 67 participants died, including 21 from suicide. Depression proved to be a reliable predictor of suicide risk. In a 2023 correction, researchers reported that the suicide risk was 12.1 times higher for men and 16.1 times higher for women. Starting May 1, 2025, China launched a nationwide mental health hotline at 12356, available at least 18 hours per day. - Evidence grade: B - Sources:Karlsson A, Håkansson A. (2018). Gambling disorder, increased mortality, suicidality, and associated comorbidity: A longitudinal nationwide register study. Journal of Behavioral Addictions, 7(4), 1091–1099. ；Karlsson A, Håkansson A. (2023). Corrigendum to: Gambling disorder, increased mortality, suicidality, and associated comorbidity. Journal of Behavioral Addictions, 12(1), 302. ；国家卫生健康委 (2024). 关于应用"12356"全国统一心理援助热线电话号码的通知（国卫医政函〔2024〕259 号）. - Notes: This grade is assigned because only one study exists, and it includes only individuals who sought specialist care — a group with relatively severe conditions. Consequently, the 15-fold suicide risk increase cannot be generalized to all gamblers. Handing over financial control to family members is a widely practiced approach, though lacking direct research support; thus it receives a C grade. Legal boundaries regarding gambling are outlined in Section 9, Article 13 (prohibiting bookmaking and online gambling). Whether family members should repay gambling debts incurred by a spouse is discussed in Section 8, Article 44 (such debts do not qualify as joint marital obligations). For guidance on responding to suicidal thoughts, refer to Section 37, Article 32 (inform a trusted person immediately). The primary beneficiaries are the gamblers themselves; however, family members who notice warning signs can also encourage them to follow these steps. ### 38. Men who have sex with men at high risk of HIV infection can significantly lower their infection risk by taking pre-exposure prophylaxis from designated HIV clinics on schedule - Cost: This is a prescription medication, so in most places it must be paid for out of pocket. Prices range from several hundred to several thousand yuan. Before prescribing it, doctors must test for HIV, kidney function, and hepatitis B. Follow-up tests are required every three months. The main challenge is remembering to take the pills every day without fail. - In plain terms: People who aren’t yet infected can take an antiviral drug called pre-exposure prophylaxis to protect themselves. Those who take it consistently cut their risk of infection by more than 70%. On the other hand, people who take it intermittently see almost no benefit. Because it’s a prescription drug, a medical checkup is mandatory before obtaining it, and regular follow-ups are necessary thereafter. - Benefit: This medication is a fixed-dose combination of emtricitabine and tenofovir. In the iPrEx trial, 2,499 men who have sex with men and transgender women were assigned to either take this drug daily or receive a placebo. The group taking the medication saw a 44% reduction in infections (95% CI 15–63). Among participants whose blood tests confirmed they were taking the drug, the protective effect was even stronger. The UK’s PROUD trial involved 544 men who have sex with men; those who started treatment immediately had an 86% lower infection rate compared to those who delayed treatment for a year (90% CI 64–96). France’s IPERGAY trial evaluated on-demand dosing before and after sex; results showed an 86% drop in infections (95% CI 40–98). A meta-analysis compiled by WHO concluded that overall, the relative risk of infection dropped to 0.49 (0.33–0.73, roughly a 51% reduction). In trials where adherence exceeded 70%, the relative risk fell to 0.30 (0.21–0.45, about a 70% reduction); when adherence stayed below 40%, the relative risk was 0.95, essentially indicating no effect. In August 2020, China’s National Medical Products Administration approved this drug for pre-exposure prophylaxis use in adults and adolescents weighing at least 35 kg (both domestically and internationally). - Evidence grade: A - Sources:Grant RM, Lama JR, Anderson PL, et al. (2010). Preexposure chemoprophylaxis for HIV prevention in men who have sex with men. New England Journal of Medicine, 363(27), 2587–2599. ；McCormack S, Dunn DT, Desai M, et al. (2016). Pre-exposure prophylaxis to prevent the acquisition of HIV-1 infection (PROUD): effectiveness results from the pilot phase of a pragmatic open-label randomised trial. The Lancet, 387(10013), 53–60. ；Molina JM, Capitant C, Spire B, et al. (2015). On-demand preexposure prophylaxis in men at high risk for HIV-1 infection. New England Journal of Medicine, 373(23), 2237–2246. ；Fonner VA, Dalglish SL, Kennedy CE, et al. (2016). Effectiveness and safety of oral HIV preexposure prophylaxis for all populations. AIDS, 30(12), 1973–1983. ；Xu JJ, Huang XJ, Liu XC, et al. (2020). Consensus statement on human immunodeficiency virus pre-exposure prophylaxis in China. Chinese Medical Journal, 133(23), 2840–2846. （中文版《中国 HIV 暴露前预防用药专家共识》）；World Health Organization (2019). What's the 2+1+1? Event-driven oral pre-exposure prophylaxis to prevent HIV for men who have sex with men (WHO/CDS/HIV/19.8). ；国务院办公厅 (2024). 中国遏制与防治艾滋病规划（2024—2030 年）. - Notes: The participants in these trials were primarily men who have sex with men; therefore, they are the group most encouraged to seek this treatment. Others at high risk of infection can also consult doctors to determine suitability. Prior to prescribing, it is essential to confirm that patients are not already infected; taking the medication while infected can foster viral resistance. Self-test results cannot be used as a basis for prescription. For individuals with hepatitis B, discontinuing treatment may trigger a flare-up, so testing is mandatory beforehand. WHO currently recommends on-demand dosing only for men who have sex with men engaging in sex fewer than twice a week; the regimen involves taking two tablets 2–24 hours prior to sex, followed by one tablet 24 and 48 hours afterward. Women and hepatitis B carriers must adhere to daily dosing. Trials involving on-demand dosing reported more gastrointestinal and kidney-related side effects than placebo groups; hence, regular medical checkups are indispensable. Since 2019, China has been piloting this program among men who have sex with men; official plans for 2024 emphasize “standardized implementation.” No nationwide free distribution program has been confirmed. Prospective patients should call local disease control centers to identify designated HIV clinics or STD/AIDS outpatient departments offering this treatment. Importantly, this medication does not protect against sexually transmitted infections such as syphilis or gonorrhea; condoms must still be used consistently, as noted in Section 30 of this chapter. In cases where exposure has already occurred, emergency post-exposure prophylaxis is available per Section 13, Item 38 (within 72 hours). Ultimately, this treatment safeguards both the individual and their sexual partners. ### 39. Women aged 65 and older should have a dual-energy X-ray absorptiometry (DXA) bone density test; postmenopausal women with osteoporosis risk factors need not wait until 65 - Cost: A hospital DXA scan of the lumbar spine and hip takes a few minutes lying down. Out-of-pocket cost is usually 100–200 yuan, varying by region. Heel ultrasound at a checkup can screen but cannot diagnose. - In plain terms: Women aged 65 and older, and postmenopausal women with osteoporosis risk factors, should have bone density measured once. When screening starts with fracture-risk assessment and treats those at high risk, hip fractures fall by about 17%. That works out to about 5 fewer hip fractures per 1,000 people screened. Overall mortality did not change. - Benefit: The U.S. Preventive Services Task Force 2025 recommendation is osteoporosis screening for women aged 65 and older (Grade B). Postmenopausal women under 65 at high fracture risk by assessment should also be screened (Grade B). Evidence for men is insufficient; no recommendation. The evidence review for that guidance pooled 3 randomized trials with 42,009 older European women. Screening meant assessing fracture risk first, measuring bone density in those at high risk, and treating those found high risk. Hip fractures in the screening group were about 17% lower (RR 0.83, 95% CI 0.73 to 0.93). In absolute terms, screening avoided 5 hip fractures per 1,000 people. In the UK SCOOP trial of 12,483 women aged 70 to 85, hip fractures in the screening group were about 28% lower (HR 0.72, 95% CI 0.59 to 0.89); mortality did not differ. The Chinese Medical Association 2017 guideline recommends DXA for women aged 65 and older and men aged 70 and older, and earlier when osteoporosis risk factors are present. In a 2017–2018 national survey, osteoporosis prevalence among adults over 40 was 20.6% in women and 5.0% in men (China). - Evidence grade: A - Sources:US Preventive Services Task Force, Nicholson WK, Silverstein M, et al. (2025). Screening for Osteoporosis to Prevent Fractures: US Preventive Services Task Force Recommendation Statement. JAMA. ; Kahwati LC, Kistler CE, Booth G, et al. (2025). Screening for Osteoporosis to Prevent Fractures: A Systematic Evidence Review for the US Preventive Services Task Force. JAMA. ; Shepstone L, Lenaghan E, Cooper C, et al. (2018). Screening in the community to reduce fractures in older women (SCOOP): a randomised controlled trial. The Lancet. ; 中华医学会骨质疏松和骨矿盐疾病分会 (2017). 原发性骨质疏松症诊疗指南(2017). 中华骨质疏松和骨矿盐疾病杂志, 10(5), 413-443（表 5 骨密度测量的临床指征）. ; Wang L, Yu W, Yin X, et al. (2021). Prevalence of Osteoporosis and Fracture in China: The China Osteoporosis Prevalence Study. JAMA Network Open. - Notes: Controversy: SCOOP's prespecified primary outcome was all osteoporotic fractures; the screening group did not show a clear reduction (HR 0.94, 95% CI 0.85 to 1.03)—only hip fractures fell. All three trials used "assess risk, then measure bone density"; none compared bone density testing alone. The evidence review also estimated 11.8% to 24.1% overdiagnosis—people who would never have fractured from this cause in their lifetime. For men, the U.S. says evidence is insufficient; China's guideline sets age 70—follow your doctor. This item is about whether bone can survive a fall; avoiding falls themselves is item 13 (balance and leg strength)—do both. After osteoporosis is found, see item 40 (treat with medication). Primary beneficiaries are you and your parents. ### 40. If you are diagnosed with osteoporosis, or have fractured from a minor fall, ask a doctor for osteoporosis medication and keep taking it—do not treat calcium supplements as a substitute - Cost: Prescription required; use continues for years. Common options include once-weekly oral drugs and once-yearly infusions. Bone density should be rechecked yearly at first, then every 1 to 2 years once stable. The hard part is continuing when you feel fine. - In plain terms: If osteoporosis is confirmed, or you have already fractured from a light fall, following a doctor's drug plan cuts hip fractures by about half and symptomatic spine fractures by a bit more than half. In older people who start yearly infusion within 90 days after hip-fracture surgery, new fractures over two years fall by about 35%. Calcium alone cannot replace these drugs. - Benefit: Fragility fracture means a fracture from minor trauma or everyday activity. The Chinese Medical Association 2017 guideline lists three groups for treatment: prior fragility fracture of spine or hip; bone density T-score −2.5 or lower regardless of prior fracture; or low bone mass plus fragility fracture of wrist, upper arm, or pelvis, or high calculated fracture risk. The guideline states: "There is currently insufficient evidence that calcium supplementation alone can replace other anti-osteoporosis drug therapy." Cochrane's 2025 update on alendronate in postmenopausal women with osteoporosis or prior fracture found hip fractures about 51% lower in the treated group (RR 0.49, 95% CI 0.25 to 0.96) and symptomatic vertebral fractures about 55% lower (RR 0.45, 95% CI 0.28 to 0.73). The HORIZON trial enrolled 2,127 people mean age 74.5 after hip-fracture surgery; yearly zoledronic acid starting within 90 days post-op, median follow-up 1.9 years. New fractures fell from 13.9% to 8.6% (about 35% relative reduction). Death fell from 13.3% to 9.6% (about 28% relative reduction). The guideline notes about 20% of people die from complications within one year after hip fracture. In the 2017–2018 national survey, only 1.4% of women and 0.3% of men with diagnosed osteoporosis or prior fracture were on medication (China). - Evidence grade: A - Sources:中华医学会骨质疏松和骨矿盐疾病分会 (2017). 原发性骨质疏松症诊疗指南(2017). 中华骨质疏松和骨矿盐疾病杂志, 10(5), 413-443（表 10 抗骨质疏松症药物治疗适应证；钙剂一节；疗效监测一节）. ; Wells GA, Hsieh SC, Peterson J, et al. (2025). Alendronate for the primary and secondary prevention of osteoporotic fractures in postmenopausal women. Cochrane Database of Systematic Reviews. ; Lyles KW, Colón-Emeric CS, Magaziner JS, et al. (2007). Zoledronic acid and clinical fractures and mortality after hip fracture. New England Journal of Medicine. ; Cummings SR, Lui LY, Eastell R, Allen IE (2019). Association Between Drug Treatments for Patients With Osteoporosis and Overall Mortality Rates: A Meta-analysis. JAMA Internal Medicine. ; Kahwati LC, Kistler CE, Booth G, et al. (2025). Screening for Osteoporosis to Prevent Fractures: A Systematic Evidence Review for the US Preventive Services Task Force. JAMA. ; Wang L, Yu W, Yin X, et al. (2021). Prevalence of Osteoporosis and Fracture in China: The China Osteoporosis Prevalence Study. JAMA Network Open. - Notes: Controversy: A meta-analysis of 38 trials did not show these drugs lowering overall mortality (RR 0.98, 95% CI 0.91 to 1.05). Zoledronic acid alone was also not significant (RR 0.88, 95% CI 0.68 to 1.13). The authors concluded these drugs should be used to prevent fractures, not to cut death rates. Cochrane rated those fracture estimates low to moderate certainty. In women without prior fracture and lower risk, alendronate did not clearly reduce hip fractures (RR 0.76, 95% CI 0.43 to 1.32). Rare harms such as jaw osteonecrosis and atypical femur fracture may not show up in trials of a few years—keep follow-up visits and do not change dose on your own. Injection versus pills depends on the doctor. How to find osteoporosis is item 39 (bone density testing). Primary beneficiaries are you and your parents.