CB Chow

1. Overview

During the last two decades, injury and poisoning have surpassed diseases as the leading cause of death and disability in children and youth in Hong Kong.¹ It is also the leading cause of childhood disability. Since 1961, the rate of injury deaths among children under 15 years of age declined by 75% whereas death rates for other diseases declined by 95%. (Table 1)

Injuries are not random and uncontrollable events of fate. They can be studied in an organized fashion using the three methods of scientific investigation: epidemiology, biomechanics and behavioural science. By understanding injuries, interventions can be developed and implemented to prevent or limit the extent of a given injury. In fact, more than 90% of these injuries are predictable and preventable.

2. Injury Epidemiology

Mortality statistics on injuries are accurate and readily available in Hong Kong. Each mortality arising from injuries is certified by a coroner and duly recorded. During the period 1990 to 1996, about 50-80 children under 15 years of age died as a result of injuries each year. In 1996, injury and poisoning causes about 2% of the deaths among 0-1 years, 25% of the deaths among children aged 1-4 years and 30% of all deaths of children aged 4 to 14 years of age.¹ Road traffic accidents, drowning and submersion and accidental falls accounted for 30%, 20% and 20% respectively of all deaths from unintentional injury in children aged under 15 years of age. Accidental poisoning is a uncommon cause of death. (Table 2) The average annual mortality rates for the period 1990 to 1995 were 4.8 per 100,000 for boys and 3.0 per 100,000 for girls. The highest risk group was in children under 5 (5.4 per 100,000) and lowest in children aged 5-9 (3.3 per 100,000) and rise to 3.9 per 100,000 in the 10-14 years of age. Boys predominated with male to female death ratio of 3:2.² However, mortality figures are just "tip of the iceberg" and will not give a complete picture of the injury problem.

Injury morbidity data are much more difficult to obtain and accurate morbidity figure on injury and poisoning is not available in Hong Kong. Although all public and private hospital discharges are assigned ICD codes, external causes (E-code) are frequently not coded and breakdown by age is not available in hospital statistics. A study in one regional hospital reported that trauma accounted for 65% of surgical and orthopaedic admissions of children under 12 years of age and 15% required operation under general anaesthesia.³ With computerization of hospital records, these data may be available in the near future.

There is some indication that most childhood injuries were treated at Accident & Emergency Departments (A&E) rather than by private practitioners.⁴ Thus A&E attendance might be an indicator on the prevalence of childhood injuries. Statistics from Hospital Authority indicated each year about 60,000 children under 15 years of age attended A&E for trauma.⁵ Injuries account for about 30% of paediatric attendance at Accident and Emergency Department of a regional hospital and 20% of all hospitalisation among children.6 It has been estimated that about 2.9% of children will be admitted to hospital for injuries at least once before their fourth birthday.⁷ A recent survey conducted in Prince of Wales Hospital indicated that about 55/1000 children per year attended A&E for injury.⁸

However, territory-wide data on the nature of injuries in children per se is not available. Data from a prospective study at the Accident and Emergency Department in a regional hospital indicated that accidental falls accounted for 44% (falls from beds or furniture 10.6%), traffic accidents 7.3%, sports injury 6.0%, foreign body to eyes or other orifices 5.6%, bicycle injuries 3.8%, burns and scalds 1.1%, poisoning 0.55 and other injuries 31.7%. A recent study showed similar results.(Table 3, 4)^6,8 More than half of injuries in children occurred at home (52%) followed by road (19%), school (12%) and playground (9%).⁶ Majority of the injuries were not serious and 99% had abbreviated injury scale of 2 or less.⁸ About a third needed hospitalisation.

2.1 General

Hong Kong, being a small, highly urbanized and very densely populated place, the pattern of injuries shows some special characteristics. The very over-crowded environment leads to preponderance of high-rise buildings, the use of double-decked beds, camp beds, folding chairs and folding tables by many families to save space. Hong Kong is having the highest death rate from accidental falls but lowest death rate from accidental poisoning compared with other developed countries.⁸ From 1985 to 1989, 8 children suffocated to death because of being trapped in folding tables. Many children are left unattended at home due to the increasing number of working parents. In a recent survey (1997) 58.7% and 34.2% of domestic households had left one and two children aged 12 and below unattended at home in the past 7 days for a period of 2-4 hours.⁹ Coroners statistics indicated that from 1989-1994 a total of 113 unattended children died in Hong Kong most of them in horrible circumstance. Poisoning is relatively uncommon in Hong Kong. Some types of injuries show clear seasonal patterns - fractures are more common during summer holidays and burns at midautumn festival.^10,11 There are several hospital based studies on different aspect of childhood injuries e.g. head, eye, sport injuries and foreign body ingestion etc. but most are descriptive in nature. Pre-event or event risk factors were not analysed.^10-17

2.2 Traffic raffic accidents

Traffic accident is the major cause of death in children. The number of cars is increasing rapidly in the past decade while casualty rate from traffic accidents declined by 13% in children. On average about 6-7 children are reported injured on the road every day. Boys aged 10-14 years are at the highest risk of traffic injuries. The peak period for traffic accidents in children occur around 1 pm and 4-6 pm coinciding with school dispersal hour. Over half (56%) of childhood traffic injuries occur in pedestrians. Pedestrian casualties were in general associated with higher percentage of fatalities and serious injuries (31%) compared to vehicle occupant injuries (16%). Bicycle riding is more a recreational activities than mean of transport in Hong Kong. However, children are more prone to bicycle injuries. It is a common cause of fracture and about 36% is serious.

2.3 Drowning and submersion

Swimming is Hong Kong's most popular pastime during summer. Each year some 13 million people visited the beaches and another 6 million enjoyed the numerous public swimming pools managed by the two municipal councils. Drowning is the second largest cause of deaths in children dying from injuries. Boys aged 5-9 years of age are most vulnerable. Data on the places and circumstances in which drowning occurred is lacking. Recently children had been drowned in public swimming pools. Poor design or inadequate warning had been incriminated as contributing factors. More information and study on this is required.

2.4 Falls

Falls are third commonest cause of childhood injury deaths. It is the commonest cause of injury deaths in children under 5 years of age. Most of deaths are from falls from high buildings (60%). Falls accounted for about half of injuries seen at Accident and Emergency Department. Most of them occurred at home in children under 5 years of age. Falling off from beds especially from double-decked ones is a common cause of head injury.¹⁴

Many of the falls involved infants sleeping in beds without guards.

2.5 Burn and scald

Though not a common cause of death, burn and scald in children often involve face and extremities resulting in permanent disability or disfigurement. Each year about two thousands children are seen at A&E for burn or scald. About 90% are due to scald by hot liquid and majority occurs in children under 4 years of age.11 Every year during the mid-autumn festival, many children are burnt on face or extremities form playing with boiling wax.

2.6 Fire

Hong Kong, being very densely populated with highrise buildings, fire is a major risk to lives. The number of fire calls is increasing over the years, while the number of people injured and died remained rather steady. Each year there are about 50-60 major fires at No. 3 alarm and over. The major causes of fires were careless handling or disposal of smoking materials, overturned cooking stoves and electrical faults. In 1994, 183 cases of fire were due to children playing with matches. Of the deaths from fire, most were children under 5 years of age occurring in private dwellings.

2.7 Accidental poisoning

Deaths due to poisoning are uncommon in Hong Kong probably due to crowded environment and children could be observed more closely. The pattern of poisoning is changing - in the 1960s, saliylate, kerosene and pesticides were major agents involved. Now, drugs taken by parents or relatives are the main causative agents (table 3).^12,13

2.8 Playgrounds

Figures on playground injuries are not available from the Urban and Regional Councils. In a one-year surveillance performed at the Accident and Emergency Department revealed that about 8.7% of childhood injuries occurred at playground, mostly due to falls from height or on level grounds.

2.9 Sports injury

Data on sports injuries are lacking. A recent study at the Sports Injury Clinic in Prince of Wales Hospital and the Sports Medicine Department in the Hong Kong Sports Institute indicated that gymnastic and track events were the two sports with the highest number of injuries. Lack of warm up exercise and protective aids were common factors associated with injuries.¹⁸ In A&E setting, it accounted for 7.4% of childhood injuries and ball games and skating were the major causes.⁶

Population-based injury statistics are ideal but are often difficult to obtain. To obviate very high cost in getting an accurate estimate of prevalence of childhood injuries and yet be able to identify most, if not all of risk factors a "event enumerative approach" using social research principles towards a numerical convergence to complete exhaustiveness can be adopted. In an ongoing large-scale hospital-based research, a list of event descriptors was derived through a "saturation" process from more than 400 actual injury cases reported to an accident and emergency department in Hong Kong. The events were grouped basing on age, sex and the six causative factors - (1) physical hazards (2) behaviour hazards of carer (3) behaviour hazards of peer (4) child in dangerous state (5) own dangerous act of the child (6) mere accident. A list of 150 event descriptors had been developed for use in prevention programme.¹⁹

2.10 Suicide

Suicide deaths had shown little significant change over the past decade across the various age groups (table 4)²⁰ In a survey of 563 school students aged 11 to 20 years, 36.4% and 7.7% indicated had ever though about committing suicide and ever attempted to commit it respectively. ²¹

2.11 Drug ab abuse use

Exact estimate on the prevalence of drug abuse is lacking. From the available data, the number of young drug abusers in Hong Kong probably is small. In the study by Education Department, of the 452,267 primary student studied, 1,054 (0.23%) were estimated to be in the at-risk group, 153 (0.03%) in the occasional drug abuser group and 76 (0.02%) in the habitual drug abuser group. Whereas of the 439,414 secondary school students, 9.194 (2.1%) were estimated to be in the ate risk group, 2,197 (0.46%) in the occasional drug abuser group, and 588 (0.12%) in the habitual drug abuser group.²¹ However, according to the 38th report of the Central Registry of Drug Abuse of the Narcotic Division, an upward trend was noticed in the number of newly reported drug abusers since 1989 in the youth population (table 5).²² Heroin continued to be the most popular drug of abuse, followed by Cannabis and cough medicine. Friends and drug-pushers were the main source of drugs. ²²

3. Injury preventive measures undertaken in Hong Kong

The identification of causal factors and high risk groups are important for designing appropriate preventive interventions - to focus on important/serious injuries problems and high risk groups. Such measures should aim at preventing the injury from occurring (pre-event) in the first place, diminishing the damage caused by the injury event once it occurs (event) or limiting the long-term sequel of the injury (post-event).

Good epidemiological data on childhood injuries are not available in Hong Kong. Preventive measures undertaken are fragmented and reactive and most have not been evaluated.

3.1 Child product-related injuries

The Toys and Children Products Safety Bill has been passed in 1993. The bill does introduce an element of protection, that toys and children products must conform to certain standards or face penalty. But penalty will only be forthcoming when some injuries have occurred to a child and the product happen to be found to be unsafe by the Custom and Excise Department. Many of the beds for young children, baby walkers, pushchairs and prams available and on sale in Hong Kong have been found by the Consumer Council to be not up to safety standard! There is no figure on child product-related injuries in Hong Kong.

3.2 Children left unattended at home

Many children are left unattended at home due to the increasing number of working parents.

On October 1991, the Government published a public Consultation Paper on Measures to Prevent Children from being left unattended at home. After a 3-months consultation the government concluded that childcare facilities, supportive services, public education needed to be increased and mutual help group encouraged. Nevertheless, it was considered neither desirable nor feasible to introduce any legislation to protect unattended children.

Since then, plans were introduced to increase the number of childcare centres. At present a total of 135 occasional child care units, each with three places, were provided to take care of children for brief periods during the day, allowing their families to attend to urgent business. A recent General Household Survey indicated that the utilisation rate of these centres is still low and children are often left unattended at home for prolonged period.⁹

3.3 Road safety

Every year there is a 5% increase in registered vehicles; the competition for road space became increasingly acute. The number of traffic accidents remained quite constant over the past few years despite increasing vehicle population. Traffic accident is the major cause of traumatic deaths in children. About half occurred with pedestrians. Accident records are regularly collected and analysed by police for black spot and road safety strategy formulation since 1991. Speeding and jumping red lights continued to be major problems. More advanced speed detection equipment and red light cameras are also introduced recently. Red light camera scheme - introduced in 1994 showed encouraging results in reducing the number of accidents and red light violations at signalcontrolled junction. The project will be expanded to cover more locations in 1995. Road Safety Council is an advisory body to co-ordinate all road safety matters in the territory. Legislation has been introduced to empower police officers to require a suspected drunk driver to be tested on the road-side starting December 15 1995. At present it is mandatory to wear seatbelt at the front seats. Legislation has been introduced for the mandatory fitting and wearing of rear seatbelt in private cars in June 1996. However, the legislation and enforcement on the infant seats is unsatisfactory.

The recent few reports of injuries/death to children sustained during travelling by school transportation has aroused considerable public concern. A Consultation Paper on Safety Provision of School Transport was released in September 1995. After the consultation, the Transport and Education Departments recommended that:

1. With effect from February 1997, all school buses with over 16 seats are required to have compulsory provision of escorts to take care of children.

2. With effect from August 1996, bus operators are required to provide details of their clients' information to Transport Department for application of an annual permission of bus service.

3. With effect from August 1996, all school bus must display a sign on the back of the vehicle to warn motorist that they are carrying children.

4. With effect from February 1997, all school buses and nanny vans are required to install alarm system at the front sliding doors and emergency doors.

5. With effect from February 1997, a standard bright colour will be assigned for all nanny vans.

6. With effect from February 1998, provision of sound system on buses for communication between driver and passengers (nanny and pupils) is mandatory.

7. All schools are encouraged to set up School Bus Service Committee for the monitoring of school bus services.

The Student Road Safety Patrols was founded in 1983. At the end of 1995, there are 241 teams under Road Safety Association of Hong Kong in operation for over 200 schools. The patrols give an alarming record of having no accidents during the 32 years' operation. 558 schools have organised school staff road safety patrols.

3.4 Recreation and sports

4. Conclusion and recommendations

In the 1998 Public Health Report on Unintentional Injuries in Children, the Department of Health of Hong Kong has made 27 recommendations and to achieve the following targets by the year 2005 ²:-

• Deaths from unintentional injuries to no more than 3 per 100,000 children (1990-95 baseline) 4.1 per 100,000 children).

• Annual childhood deaths caused by motor vehicle crashes to no more than 10 on average (1990-95 baseline 15 per year).

• Annual reported childhood road casualties to no more than 2000 (1990-95 baseline 2700 per year).

• Annual death rate from falls to no more than 0.6 per 100,000 children (90-95 baseline 0.8 per 100,000 children).

Injury is a major health problem in Hong Kong children. Information on the extent of the problem and their contributing factors are scarce and scattered. Preventive measures are reactive in nature, piecemeal and usually not subjected to evaluation. It is thus important that: -

1. Childhood injury prevention must be accorded high priority and child safety is given prime consideration in all policies involving children.

2. A "Childhood Injury Information System" should be set up to (1) collect, collate and generate timely and accurate information concerning the incidence, circumstances and contributing factors, severity and long term outcome of childhood injuries; (2) interpret and analyze these information to identify problems, hazards, risk groups and injury-producing behaviours; and (3) disseminate the information to relevant authorities and agencies for appropriate action.

3. Injury prevention should be recognized as major public health issue and adequate resources be allocated for research and control programmes.

4. Effective injury control requires multidisciplinary approach and community participation It should be evidence-based.24 A "Child Safety Council" should be established to steer and coordinate all activities related to childhood injury prevention.

5. Health care professionals should contribute towards injury control and support safe environment scheme by providing expertise, information and communicating the problem, public education and training of professionals.

References

1. Annual report. Department of Health, Hong Kong Government 1996.

2. Department of Health, Hong Kong. Public Health Report No.3. Viral hepatitis and Liver Cancer and Unintentional Injuries in Children, 1998;41-65.

3. Chan KM, Hung LK, Leung PC. The scene of children's trauma in Hong Kong - a preliminary survey of 3974 cases in a regional hospital. The Bulletin of the Hong Kong Medical Association. 1984; 36:127-31.

4. Lee A, Chan K, Wun YT, et al. A morbidity survey in Hong Kong 1994. The Hong Kong Practitioner 1995; 17:246-55.

5. Accident & Emergency Department Statistics 1996 - Personal communication.

6. Chow CB, Chan KH, Chiu LH. Childhood injuries in Hong Kong - a one year surveillance at an accident emergency department. HK J Paediatr (special issue) 1993; 196-212.

7. Chung SF, Lam TH. Visits to hospitals in Hong Kong children during the first four years of life. Proceeding Hospital Convention, Hong Kong Hospital Authority 1997.

8. Childhood Injury Prevention Research Group. A hospital-based childhood injury cohort study. Unpublished 1998.

9. Census and Statistics Department, Hong Kong SAR. Social data collected via the General Household Survey Special Topics Report No. 17 - Leaving children aged 12 and below unattended at home. Printing Department, HKSAR 1997;1-22 .

10. Cheng CY, Chen WY. Limb fracture pattern in 2500 children under age 12. Journal of the Hong Kong Medical Association 1991; 43:230-34.

11. Cheng CY, Lam CL, Leung PC, Mak DP. An epidemiological study on burn injuries in Hong Kong. Journal of the Hong Kong Medical Association 1990; 42:26-8.

12. Chan TKY, Critchley JAJ. Childhood poisoning in Hong Kong. HKMJ 1996; 2:191-5.

13. Chow CB, Cheung MW, Lui KM, Leung NK. Poisoning and drug overdose in Hong Kong children. HK J Paediatr 1993;10:113-7.

14. Goh KYC, Zhu XL, Poon WS. Features of Pediatric Head Injury in Hong Kong. JNK Hsiang, 1997.

15. Hsian JNK, Cheung TKW, Goh KYC, Zhu XL, Poon WS. Features of head injury at Prince of Wales Hospital, Hong Kong, from 1989 to 1993. HKMJ 1996; 2:141-5.

16. Chung ECH, Hon TYW, Leung KP, Lau FL. Accidental ingestion of foreign bodies in children - a 4-month survey at United Christian Hospital. HK J Paediatr (new series) 1997;2:41-3.

17. Chung CF. Epidemiology of severe childhood eye injuries that require hospitalization. HK J Paediatr (new series) 1998.

18. Yeung J, Chan KM, Chieng P, Li CK, Yuan Y, Wong YY. Epidemiological Study on Sports Injury in Hong Kong 1997.

19. Hong Kong Childhood Injury Prevention Research Group. Two-part prospective study on childhood injury and its prevention in Hong Kong 1998.

20. Yip PSF, Ho TP, Hung SF, Laidler KJ, Leung PWL. Youth Suicides in Hong Kong. Befrienders International 1998.

21. A Study of the values and self-destructive behaviour of local secondary school students. Breakthrough, Hong Kong 1993.

22. Report of a study on identifying the at-risk group among young people for direct service of preventive education 1996 Education Department Hong Kong.

23. Central registry of drug abuse: 38th report (Jan 1987 - Jun 1996) Narcotics Division, Hong Kong 1996.

24. Youth in Hong Kong a Statistical Profile 1997 Working Group, Commission on Youth 1997.

25. Preventing unintentional injuries in childhood and young adolescents. Nuffield Institute for Health, University of Leeds, NHS Centre for Reviews and Dissemination, University of York. Eff Health Care 1996; 2:1-16.